NCBI Conserved Domain Search

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 128.28 E-value: 5.67e-35

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAED-EEVVFECRAAGVPEPKISWIHNGKPIEQstPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd20978     1 PKFIQKPEKNVVVKGgQDVTLPCQVTGVPQPKITWLHNGKPLQG--PMERATVEDGTLTIINVQPEDTGYYGCVATNEIG 78

                          90
                  ....*....|
gi 281360617  418 YVYKDVYLNV 427
Cdd:cd20978    79 DIYTETLLHV 88

Bravo-like intracellular region; This is the very C-terminal intracellular region of neural adhesion molecule L1 proteins that are also known as Bravo or NrCAM. It lies upstream of the IG and Fn3 domains and has the highly conserved motif FIGEY. The function is not known.

Pssm-ID: 464016 Cd Length: 88 Bit Score: 108.18 E-value: 6.08e-28

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  1155 RRNRGGKYDVHDRELANGRRDYP--EEGGFHEYS----QPLDNksaGRQSVSSANKPGVESDTDSMAEYGDGDTGM-NED 1227
Cdd:pfam13882    1 KRNKGGKYSVKEKEDAHGDPEDQpmDEDAFGEYSdldeKPLKS---SQPSLSSDSKLVDSDSTDSLDDYGDGDGGQfNED 77

                           90
                   ....*....|
gi 281360617  1228 GSFIGQYGRK 1237
Cdd:pfam13882   78 GSFIGQYGGK 87

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 85.58 E-value: 6.54e-20

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  340 YFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLGYV 419
Cdd:cd04978     1 YWIIEPPSLVLSPGETGELICEAEGNPQPTITWRLNGVPIEPAPEDMRRTVDGRTLIFSNLQPNDTAVYQCNASNVHGYL 80


                  ....*...
gi 281360617  420 YKDVYLNV 427
Cdd:cd04978    81 LANAFLHV 88

Immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains NrCAM [Ng(neuronglia)CAM-related cell adhesion molecule], which is primarily expressed in the nervous system, and human neurofascin. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409396 [Multi-domain] Cd Length: 94 Bit Score: 84.77 E-value: 1.33e-19

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   29 PRITKQPAPGELLFkvaqqnkeSDNPFIIECEADGQPEPEYSWIKNGKKFDwQAYDNRMLRQPGRGTLVITI---PKDED 105
Cdd:cd05733     1 PTITEQSPKDYIVD--------PRDNITIKCEAKGNPQPTFRWTKDGKFFD-PAKDPRVSMRRRSGTLVIDNhngGPEDY 71

                          90       100
                  ....*....|....*....|...
gi 281360617  106 RGHYQCFASNEFGTATSNSVYVR 128
Cdd:cd05733    72 QGEYQCYASNELGTAISNEIRLV 94

Second immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structures of this group show that the second Ig domain lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules, including vascular (VCAM), intercellular (ICAM), neural (NCAM) and mucosal addressin (MADCAM) cell adhesion molecules, as well as junction adhesion molecules (JAM).

Pssm-ID: 409557 Cd Length: 101 Bit Score: 82.30 E-value: 1.21e-18

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  137 DEAAKTLEA--VEGEPFMLKCAAPDGFPSPTVNWMIQESIDGSI-KSINNSRMTLDPEGNLWFSNVTREDASSDFYYACS 213
Cdd:cd20965     4 DPQVKTKEKkpVEGKPFKLDCNVPPGYPKPTIEWKKQLVSDSSKaDTILDRRITISPNGDLYFTNVTKEDVSTDYKYVCV 83


                  ...
gi 281360617  214 ATS 216
Cdd:cd20965    84 AKT 86

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 78.07 E-value: 2.64e-17

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQStpnPRRTVTDN----TIRIINLVKGDTGNYGCNATN 414
Cdd:pfam07679    1 PKFTQKPKDVEVQEGESARFTCTVTGTPDPEVSWFKDGQPLRSS---DRFKVTYEggtyTLTISNVQPDDSGKYTCVATN 77

                           90
                   ....*....|...
gi 281360617   415 SLGYVYKDVYLNV 427
Cdd:pfam07679   78 SAGEAEASAELTV 90

Immunoglobulin (Ig)-like domain of human neurofascin (NF); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of human neurofascin (NF). NF belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and a cytoplasmic domain. NF has many alternatively spliced isoforms having different temporal expression patterns during development. NF participates in axon subcellular targeting and synapse formation, however little is known of the functions of the different isoforms. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409459 Cd Length: 95 Bit Score: 76.94 E-value: 8.79e-17

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   29 PRITKQPAPGELLfkvaqqnKESDNpFIIECEADGQPEPEYSWIKNGKKFDwQAYDNRMLRQPGRGTLVITI---PKDED 105
Cdd:cd05875     1 PTITKQSAKDYIV-------DPRDN-ILIECEAKGNPVPTFHWTRNGKFFN-VAKDPRVSMRRRSGTLVIDFrggGRPED 71

                          90       100
                  ....*....|....*....|....
gi 281360617  106 -RGHYQCFASNEFGTATSNSVYVR 128
Cdd:cd05875    72 yEGEYQCFARNKFGTALSNKIRLQ 95

First immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The first Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules, including vascular (VCAM), intercellular (ICAM), neural (NCAM) and mucosal addressin (MADCAM) cell adhesion molecules, as well as junction adhesion molecules (JAM).

Pssm-ID: 409571 Cd Length: 91 Bit Score: 76.45 E-value: 1.03e-16

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   29 PRITKQPApgELLFKvaqqnkeSDNPFIIECEADGQPEP-EYSWIKNGKKFDWQAyDNRMLRQpGRGTLVITIPKDEDRG 107
Cdd:cd20979     1 PVLKEQPA--EVLFR-------EGQPTVLECVTEGGDQGvKYSWLKDGKSFNWQE-HNVAQRK-DEGSLVFLKPQASDEG 69

                          90       100
                  ....*....|....*....|..
gi 281360617  108 HYQCFASNEFGTATSNSVYVRK 129
Cdd:cd20979    70 QYQCFAETPAGVASSRVISFRR 91

Sixth immunoglobulin (Ig) domain of contactin; The members here are composed of the sixth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409359 Cd Length: 102 Bit Score: 76.05 E-value: 2.05e-16

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  521 TRITQEPQNYEVAAGQSATFRCNEAHDDTLEIEIDWWKDGQSIDFEA-----QPRFVKTNDNSLTIAKTMELDSGEYTCV 595
Cdd:cd04970     3 TRITLAPSNADITVGENATLQCHASHDPTLDLTFTWSFNGVPIDLEKieghyRRRYGKDSNGDLEIVNAQLKHAGRYTCT 82

                          90       100
                  ....*....|....*....|
gi 281360617  596 ARTRLDEATARANLIVQDVP 615
Cdd:cd04970    83 AQTVVDSDSASATLVVRGPP 102

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 74.80 E-value: 3.91e-16

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617  446 GRNVTIKCRVNGSPKPLVKWLRASNWLT-GGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSLVV 517
Cdd:cd04969    17 GGDVIIECKPKASPKPTISWSKGTELLTnSSRICILPDGSLKIKNVTKSDEGKYTCFAVNFFGKANSTGSLSV 89

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 73.00 E-value: 1.28e-15

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   525 QEPQNYEVAAGQSATFRCNeAHDDTLEIEIDWWKDGQSIDFEAQ--PRFVKTNDNSLTIAKTMELDSGEYTCVARTRLDE 602
Cdd:pfam00047    1 SAPPTVTVLEGDSATLTCS-ASTGSPGPDVTWSKEGGTLIESLKvkHDNGRTTQSSLLISNVTKEDAGTYTCVVNNPGGS 79


                   ....*..
gi 281360617   603 ATARANL 609
Cdd:pfam00047   80 ATLSTSL 86

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 71.83 E-value: 3.42e-15

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617   431 PPTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGGR----YNVQANGDLEIQDVTFSDAGKYTCYAQN 504
Cdd:pfam13927    1 KPVITVSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGStrsrSLSGSNSTLTISNVTRSDAGTYTCVASN 78

Immunoglobulin (Ig)-like domain of NrCAM (Ng (neuronglia) CAM-related cell adhesion molecule); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of NrCAM (Ng (neuronglia) CAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409458 Cd Length: 95 Bit Score: 71.94 E-value: 4.96e-15

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617   56 IIECEADGQPEPEYSWIKNGKKFDWQAyDNRMLRQPGRGTLVITIPKDED----RGHYQCFASNEFGTATSNSVYVR 128
Cdd:cd05874    20 VIQCEAKGKPPPSFSWTRNGTHFDIDK-DPKVTMKPNTGTLVINIMNGEKaeayEGVYQCTARNERGAAVSNNIVIR 95

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 70.89 E-value: 7.14e-15

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  438 PAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSLVV 517
Cdd:cd05725     4 PQNQVVLVDDSAEFQCEVGGDPVPTVRWRKEDGELPKGRYEILDDHSLKIRKVTAGDMGSYTCVAENMVGKIEASATLTV 83

Fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule); The members here are composed of the fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six IG-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409454 Cd Length: 89 Bit Score: 71.17 E-value: 7.46e-15

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  340 YFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLGYV 419
Cdd:cd05868     1 YWITAPTNLVLSPGEDGTLICRANGNPKPSISWLTNGVPIEIAPTDPSRKVDGDTIIFSKVQERSSAVYQCNASNEYGYL 80


                  ....*...
gi 281360617  420 YKDVYLNV 427
Cdd:cd05868    81 LANAFVNV 88

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 70.99 E-value: 7.67e-15

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  341 FTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIeqSTPNPRRTVTDN-TIRIINLVKGDTGNYGCNATNSLGYV 419
Cdd:cd20952     2 ILQGPQNQTVAVGGTVVLNCQATGEPVPTISWLKDGVPL--LGKDERITTLENgSLQIKGAEKSDTGEYTCVALNLSGEA 79


                  ....*...
gi 281360617  420 YKDVYLNV 427
Cdd:cd20952    80 TWSAVLDV 87

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 70.36 E-value: 1.20e-14

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLT-GGRYNVQANGD---LEIQDVTFSDAGKYTCYAQNKFG 507
Cdd:pfam07679    1 PKFTQKPKDVEVQEGESARFTCTVTGTPDPEVSWFKDGQPLRsSDRFKVTYEGGtytLTISNVQPDDSGKYTCVATNSAG 80

                           90
                   ....*....|
gi 281360617   508 EIQADGSLVV 517
Cdd:pfam07679   81 EAEASAELTV 90

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 69.90 E-value: 1.48e-14

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617   339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPI-EQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATN 414
Cdd:pfam13927    2 PVITVSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPIsSGSTRSRSLSGSNSTLTISNVTRSDAGTYTCVASN 78

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 66.97 E-value: 1.07e-13

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617  356 VVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDN-TIRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd00096     1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELGNgTLTISNVTLEDSGTYTCVASNSAG 63

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 67.53 E-value: 1.23e-13

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617    438 PAAVSTVDGRNVTIKCRVNGSPKPLVKWLR-ASNWLT-GGRYNVQANGD---LEIQDVTFSDAGKYTCYAQNKFGEIQAD 512
Cdd:smart00410    1 PPSVTVKEGESVTLSCEASGSPPPEVTWYKqGGKLLAeSGRFSVSRSGStstLTISNVTPEDSGTYTCAATNSSGSASSG 80


                    ....*
gi 281360617    513 GSLVV 517
Cdd:smart00410   81 TTLTV 85

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 67.53 E-value: 1.33e-13

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISeAPAAVSTVD---GRNVTIKCRVNGSPKPLVKWLRASNWLTGG--RYNVQANGD-LEIQDVTFSDAGKYTCYAQNK 505
Cdd:cd20970     1 PVIS-TPQPSFTVTareGENATFMCRAEGSPEPEISWTRNGNLIIEFntRYIVRENGTtLTIRNIRRSDMGIYLCIASNG 79

                          90
                  ....*....|...
gi 281360617  506 -FGEIQADGSLVV 517
Cdd:cd20970    80 vPGSVEKRITLQV 92

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 67.42 E-value: 1.42e-13

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTG--GRYNVQANGdLEIQDVTFSDAGKYTCYAQNKFGE 508
Cdd:cd20978     1 PKFIQKPEKNVVVKGGQDVTLPCQVTGVPQPKITWLHNGKPLQGpmERATVEDGT-LTIINVQPEDTGYYGCVATNEIGD 79


                  ....*....
gi 281360617  509 IQADGSLVV 517
Cdd:cd20978    80 IYTETLLHV 88

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 67.05 E-value: 1.48e-13

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   918 SPVQGLDAYPLGSSAFMLHWKKPLYPNGKLTGYKIYYEEVKESyvgerrEYDPHITDPRVT-RMKMAGLKPNSKYRISIT 996
Cdd:pfam00041    1 SAPSNLTVTDVTSTSLTVSWTPPPDGNGPITGYEVEYRPKNSG------EPWNEITVPGTTtSVTLTGLKPGTEYEVRVQ 74

                           90
                   ....*....|.
gi 281360617   997 ATTKMGEGSEH 1007
Cdd:pfam00041   75 AVNGGGEGPPS 85

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 66.58 E-value: 1.50e-13

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617   55 FIIECEADGQPEPEYSWIKNGKKFDWQAYDNRMLrQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNSV 125
Cdd:cd00096     1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSRRS-ELGNGTLTISNVTLEDSGTYTCVASNSAGGSASASV 70

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 75.04 E-value: 1.56e-13

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  683 NYTFRVIAFNKIGASPPSAHSDSCTTQPDVPFKNPDNVVGQGTEPNNLVISWTPMPEIEHNAPNFHYyvswkrdiPAAAW 762
Cdd:COG3401   110 GLTSSDEVPSPAVGTATTATAVAGGAATAGTYALGAGLYGVDGANASGTTASSVAGAGVVVSPDTSA--------TAAVA 181

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  763 ENNNIFDWRQNNIVIADQPTFVKYLIKVVAINDRGESNVAaeEVVGYSGEDRPLDAPTNFTMrQITSSTSGYMAWTPVSE 842
Cdd:COG3401   182 TTSLTVTSTTLVDGGGDIEPGTTYYYRVAATDTGGESAPS--NEVSVTTPTTPPSAPTGLTA-TADTPGSVTLSWDPVTE 258

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  843 ESVrghfKGYKIQTWTENEGEegLREIHVKGDThNALVTQFKPDSKNYARILAYNGRFN-GPPSAVIDFDTPEGVPSPVQ 921
Cdd:COG3401   259 SDA----TGYRVYRSNSGDGP--FTKVATVTTT-SYTDTGLTNGTTYYYRVTAVDAAGNeSAPSNVVSVTTDLTPPAAPS 331

                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  922 GLDAYPLGSSAFMLHWKKPlyPNGKLTGYKIYYeevKESYVGERREYDPHITDPRVTRmkmAGLKPNSKYRISITATTKM 1001
Cdd:COG3401   332 GLTATAVGSSSITLSWTAS--SDADVTGYNVYR---STSGGGTYTKIAETVTTTSYTD---TGLTPGTTYYYKVTAVDAA 403

                         330       340       350       360       370
                  ....*....|....*....|....*....|....*....|....*....|
gi 281360617 1002 GEGSEHYIEKTTLKDAVNVAPATPSFSWEQLPSDNGLAKFRINWLPSTEG 1051
Cdd:COG3401   404 GNESAPSEEVSATTASAASGESLTASVDAVPLTDVAGATAAASAASNPGV 453

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 67.05 E-value: 1.89e-13

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   817 DAPTNFTMRQITSsTSGYMAWTPVseESVRGHFKGYKIQTWTENEGEEgLREIHVKGDTHNALVTQFKPDSKNYARILAY 896
Cdd:pfam00041    1 SAPSNLTVTDVTS-TSLTVSWTPP--PDGNGPITGYEVEYRPKNSGEP-WNEITVPGTTTSVTLTGLKPGTEYEVRVQAV 76


                   ....*....
gi 281360617   897 NGRFNGPPS 905
Cdd:pfam00041   77 NGGGEGPPS 85

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 66.90 E-value: 1.90e-13

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   522 RITQEPQNYEVAAGQSATFRCNEAHDDTLEIEidWWKDGQSIdfEAQPRFVKTNDN---SLTIAKTMELDSGEYTCVART 598
Cdd:pfam07679    2 KFTQKPKDVEVQEGESARFTCTVTGTPDPEVS--WFKDGQPL--RSSDRFKVTYEGgtyTLTISNVQPDDSGKYTCVATN 77

                           90
                   ....*....|...
gi 281360617   599 RLDEATARANLIV 611
Cdd:pfam07679   78 SAGEAEASAELTV 90

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 66.50 E-value: 2.93e-13

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQAN---GDLEIQDVTFSDAGKYTCYAQNKFG 507
Cdd:cd20976     1 APSFSSVPKDLEAVEGQDFVAQCSARGKPVPRITWIRNAQPLQYAADRSTCEagvGELHIQDVLPEDHGTYTCLAKNAAG 80

                          90
                  ....*....|
gi 281360617  508 EIQADGSLVV 517
Cdd:cd20976    81 QVSCSAWVTV 90

Sixth immunoglobulin (Ig) domain of contactin-2; The members here are composed of the sixth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-2-like. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. It may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module by contacts between IG domains 1 and 4, and domains 2 and 3. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-2 is also expressed in retinal amacrine cells (AC) in the developing chick retina, corresponding to the period of formation and maturation of AC processes.

Pssm-ID: 409440 Cd Length: 102 Bit Score: 66.99 E-value: 3.39e-13

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  521 TRITQEPQNYEVAAGQSATFRCNEAHDDTLEIEIDWWKDGQSIDFEA-----QPRFVKTNDNSLTIAKTMELDSGEYTCV 595
Cdd:cd05854     3 TKITLAPSSADINQGENLTLQCHASHDPTMDLTFTWSLDDFPIDLDKpnghyRRMEVKETIGDLVIVNAQLSHAGTYTCT 82

                          90       100
                  ....*....|....*....|
gi 281360617  596 ARTRLDEATARANLIVQDVP 615
Cdd:cd05854    83 AQTVVDSASASATLVVRGPP 102

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 66.06 E-value: 3.51e-13

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   251 VSRRQSLALRGKRMELFCIY-GGTPLPQTVWSKDGQRIQWSDRITQG---HYGKSLVIRQTNFDDAGTYTCDVSNGVGNA 326
Cdd:pfam00047    1 SAPPTVTVLEGDSATLTCSAsTGSPGPDVTWSKEGGTLIESLKVKHDngrTTQSSLLISNVTKEDAGTYTCVVNNPGGSA 80


                   ....*.
gi 281360617   327 QSFSII 332
Cdd:pfam00047   81 TLSTSL 86

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 65.98 E-value: 5.33e-13

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  917 PSPVQGLDAYPLGSSAFMLHWKKPLYPNGKLTGYKIYYEEVKEsyvGERREYDPhiTDPRVTRMKMAGLKPNSKYRISIT 996
Cdd:cd00063     1 PSPPTNLRVTDVTSTSVTLSWTPPEDDGGPITGYVVEYREKGS---GDWKEVEV--TPGSETSYTLTGLKPGTEYEFRVR 75


                  ....*...
gi 281360617  997 ATTKMGEG 1004
Cdd:cd00063    76 AVNGGGES 83

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 64.83 E-value: 9.71e-13

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617    345 PEIATAAEDEEVVFECRAAGVPEPKISWIHNG--KPIEQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLGYVYKD 422
Cdd:smart00410    1 PPSVTVKEGESVTLSCEASGSPPPEVTWYKQGgkLLAESGRFSVSRSGSTSTLTISNVTPEDSGTYTCAATNSSGSASSG 80


                    ....*
gi 281360617    423 VYLNV 427
Cdd:smart00410   81 TTLTV 85

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 63.50 E-value: 2.13e-12

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  449 VTIKCRVNGSPKPLVKWLRASNWLT----GGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGE 508
Cdd:cd00096     1 VTLTCSASGNPPPTITWYKNGKPLPpssrDSRRSELGNGTLTISNVTLEDSGTYTCVASNSAGG 64

Fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409453 [Multi-domain] Cd Length: 89 Bit Score: 63.76 E-value: 2.44e-12

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  340 YFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLGYV 419
Cdd:cd05867     1 YWTRRPQSHLYGPGETARLDCQVEGIPTPNITWSINGAPIEGTDPDPRRHVSSGALILTDVQPSDTAVYQCEARNRHGNL 80


                  ....*...
gi 281360617  420 YKDVYLNV 427
Cdd:cd05867    81 LANAHVHV 88

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 63.96 E-value: 2.45e-12

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617  344 EPEIATAAEDEEVVFECRAA-GVPEPKISWIHNGKPIEQSTPnPRRTVTDNTIRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd05724     3 EPSDTQVAVGEMAVLECSPPrGHPEPTVSWRKDGQPLNLDNE-RVRIVDDGNLLIAEARKSDEGTYKCVATNMVG 76

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 62.20 E-value: 6.89e-12

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617    28 PPRITKQPAPgellfkvaqQNKESDNPFIIECEADGQPEPEYSWIKNGKKFDWQAYDNRMLrQPGRGTLVITIPKDEDRG 107
Cdd:pfam13927    1 KPVITVSPSS---------VTVREGETVTLTCEATGSPPPTITWYKNGEPISSGSTRSRSL-SGSNSTLTISNVTRSDAG 70


                   ....*...
gi 281360617   108 HYQCFASN 115
Cdd:pfam13927   71 TYTCVASN 78

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 69.65 E-value: 7.48e-12

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  884 KPDSKNYARILAYNGRFNGPPSAVIDFDTPEGVPSPVQGLDAYPLGSSAFMLHWKKPlyPNGKLTGYKIYYEEVKE---S 960
Cdd:COG3401   200 EPGTTYYYRVAATDTGGESAPSNEVSVTTPTTPPSAPTGLTATADTPGSVTLSWDPV--TESDATGYRVYRSNSGDgpfT 277

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  961 YVGERREydPHITDPrvtrmkmaGLKPNSKYRISITATTKMGEGSEHYIEKTTLKDavNVAPATPSFSWEQLPSDNGLak 1040
Cdd:COG3401   278 KVATVTT--TSYTDT--------GLTNGTTYYYRVTAVDAAGNESAPSNVVSVTTD--LTPPAAPSGLTATAVGSSSI-- 343

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617 1041 fRINWLPSTEghPGTHFFTMHR-IKGETQWIRENEEKNSDYQEVGGLDPETAYEFRVVSVDGHFNTESATQEIDTNTV-- 1117
Cdd:COG3401   344 -TLSWTASSD--ADVTGYNVYRsTSGGGTYTKIAETVTTTSYTDTGLTPGTTYYYKVTAVDAAGNESAPSEEVSATTAsa 420

                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617 1118 -------EGPIMVANETVANAGWFIGmmLALAFIIILFIIICIIRRNRGGKYDVHDRELAngrrDYPEEGGFHEYSQPLD 1190
Cdd:COG3401   421 asgesltASVDAVPLTDVAGATAAAS--AASNPGVSAAVLADGGDTGNAVPFTTTSSTVT----ATTTDTTTANLSVTTG 494

                         330       340       350
                  ....*....|....*....|....*....|....*...
gi 281360617 1191 NKSAGRQSVSSANKPGVESDTDSMAEYGDGDTGMNEDG 1228
Cdd:COG3401   495 SLVGGSGASSVTNSVSVIGASAAAAVGGAPDGTPNVTG 532

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 62.25 E-value: 8.59e-12

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617    917 PSPVQGLDAYPLGSSAFMLHWKKPLYPNGklTGYKIYYeevKESYVGERREYDPHITDPRVTRMKMAGLKPNSKYRISIT 996
Cdd:smart00060    1 PSPPSNLRVTDVTSTSVTLSWEPPPDDGI--TGYIVGY---RVEYREEGSEWKEVNVTPSSTSYTLTGLKPGTEYEFRVR 75


                    ....*...
gi 281360617    997 ATTKMGEG 1004
Cdd:smart00060   76 AVNGAGEG 83

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 62.13 E-value: 9.17e-12

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  523 ITQEPQNYEVAAGQSATFRCNEAHDDTLEIEidWWKDGQSIDFEaQPRFVKTNDNSLTIAKTMELDSGEYTCVARTRLDE 602
Cdd:cd20952     2 ILQGPQNQTVAVGGTVVLNCQATGEPVPTIS--WLKDGVPLLGK-DERITTLENGSLQIKGAEKSDTGEYTCVALNLSGE 78


                  ....*....
gi 281360617  603 ATARANLIV 611
Cdd:cd20952    79 ATWSAVLDV 87

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 62.14 E-value: 1.01e-11

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  345 PEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSL-GYVYKDV 423
Cdd:cd20970     9 SFTVTAREGENATFMCRAEGSPEPEISWTRNGNLIIEFNTRYIVRENGTTLTIRNIRRSDMGIYLCIASNGVpGSVEKRI 88


                  ....
gi 281360617  424 YLNV 427
Cdd:cd20970    89 TLQV 92

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 61.50 E-value: 1.58e-11

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617   261 GKRMELFCIYGGTPLPQTVWSKDGQRIQWSDR--ITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQSfSIILNV 335
Cdd:pfam07679   15 GESARFTCTVTGTPDPEVSWFKDGQPLRSSDRfkVTYEGGTYTLTISNVQPDDSGKYTCVATNSAGEAEA-SAELTV 90

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 61.17 E-value: 2.33e-11

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAP--AAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWL-TGGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGE 508
Cdd:cd05852     1 PTFEFNPmkKKILAAKGGRVIIECKPKAAPKPKFSWSKGTELLvNNSRISIWDDGSLEILNITKLDEGSYTCFAENNRGK 80


                  ....*....
gi 281360617  509 IQADGSLVV 517
Cdd:cd05852    81 ANSTGVLSV 89

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 60.51 E-value: 4.45e-11

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRAS----NWLTGGRYNVQANGD---LEIQDVTFSDAGKYTCYAQN 504
Cdd:cd20951     1 PEFIIRLQSHTVWEKSDAKLRVEVQGKPDPEVKWYKNGvpidPSSIPGKYKIESEYGvhvLHIRRVTVEDSAVYSAVAKN 80

                          90
                  ....*....|....
gi 281360617  505 KFGEIQADGSLVVK 518
Cdd:cd20951    81 IHGEASSSASVVVE 94

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 59.82 E-value: 7.13e-11

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIeqsTPNPR--RTVTDN---TIRIINLVKGDTGNYGCNAT 413
Cdd:cd05744     1 PHFLQAPGDLEVQEGRLCRFDCKVSGLPTPDLFWQLNGKPV---RPDSAhkMLVRENgrhSLIIEPVTKRDAGIYTCIAR 77

                          90
                  ....*....|....
gi 281360617  414 NSLGYVYKDVYLNV 427
Cdd:cd05744    78 NRAGENSFNAELVV 91

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 59.88 E-value: 7.39e-11

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  245 PPVRQYVSRRQSLAlRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDRITQGHYGKSL--VIRQTNF-----DDAGTYTC 317
Cdd:cd20956     1 APVLLETFSEQTLQ-PGPSVSLKCVASGNPLPQITWTLDGFPIPESPRFRVGDYVTSDgdVVSYVNIssvrvEDGGEYTC 79

                          90
                  ....*....|....*...
gi 281360617  318 DVSNGVGNAqSFSIILNV 335
Cdd:cd20956    80 TATNDVGSV-SHSARINV 96

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 59.48 E-value: 7.63e-11

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQ 510
Cdd:cd04968     1 PSIKVRFPADTYALKGQTVTLECFALGNPVPQIKWRKVDGSPSSQWEITTSEPVLEIPNVQFEDEGTYECEAENSRGKDT 80


                  ....*..
gi 281360617  511 ADGSLVV 517
Cdd:cd04968    81 VQGRIIV 87

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 59.40 E-value: 9.55e-11

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEP--EIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQStpnPRRTVTDN-TIRIINLVKGDTGNYGCNATNS 415
Cdd:cd04969     1 PDFELNPvkKKILAAKGGDVIIECKPKASPKPTISWSKGTELLTNS---SRICILPDgSLKIKNVTKSDEGKYTCFAVNF 77

                          90
                  ....*....|..
gi 281360617  416 LGYVYKDVYLNV 427
Cdd:cd04969    78 FGKANSTGSLSV 89

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 58.49 E-value: 1.07e-10

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  265 ELFCIYGGTPLPQTVWSKDGQRIQWSD--RITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQSFSI 331
Cdd:cd00096     2 TLTCSASGNPPPTITWYKNGKPLPPSSrdSRRSELGNGTLTISNVTLEDSGTYTCVASNSAGGSASASV 70

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 58.73 E-value: 1.66e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEAPAaVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWL-TGGRYNVQANGDLEIQDVTF-SDAGKYTCYAQNKFGE 508
Cdd:cd20958     1 PPFIRPMGN-LTAVAGQTLRLHCPVAGYPISSITWEKDGRRLpLNHRQRVFPNGTLVIENVQRsSDEGEYTCTARNQQGQ 79

                          90
                  ....*....|
gi 281360617  509 IqADGSLVVK 518
Cdd:cd20958    80 S-ASRSVFVK 88

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 58.17 E-value: 2.51e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   43 KVAQQNKESDnpFIIECEADGQPEPEYSWIKNGKKFDwqayDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTA-T 121
Cdd:cd20978     9 KNVVVKGGQD--VTLPCQVTGVPQPKITWLHNGKPLQ----GPMERATVEDGTLTIINVQPEDTGYYGCVATNEIGDIyT 82


                  ....*.
gi 281360617  122 SNSVYV 127
Cdd:cd20978    83 ETLLHV 88

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 57.90 E-value: 2.89e-10

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617    527 PQNYEVAAGQSATFRCnEAHDDTlEIEIDWWKDGQSIDFEaQPRF---VKTNDNSLTIAKTMELDSGEYTCVARTRLDEA 603
Cdd:smart00410    1 PPSVTVKEGESVTLSC-EASGSP-PPEVTWYKQGGKLLAE-SGRFsvsRSGSTSTLTISNVTPEDSGTYTCAATNSSGSA 77


                    ....*...
gi 281360617    604 TARANLIV 611
Cdd:smart00410   78 SSGTTLTV 85

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 57.79 E-value: 2.99e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  526 EPQNYEVAAGQSATFRCnEAHDDTLEiEIDWWKDGQSIdfeaqP--RFVKTNDNSLTIAKTMELDSGEYTCVARTRLDEA 603
Cdd:cd05725     3 RPQNQVVLVDDSAEFQC-EVGGDPVP-TVRWRKEDGEL-----PkgRYEILDDHSLKIRKVTAGDMGSYTCVAENMVGKI 75


                  ....*...
gi 281360617  604 TARANLIV 611
Cdd:cd05725    76 EASATLTV 83

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 58.03 E-value: 3.56e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   37 PGELLFKVAQQNKEsdnpFIIECEADGQPEPEYSWIKNGKKFDWQA-YDNRMLrqpgRGTLVITIPKD-EDRGHYQCFAS 114
Cdd:cd05848     8 PDDAIFPTDSDEKK----VILNCEARGNPVPTYRWLRNGTEIDTESdYRYSLI----DGNLIISNPSEvKDSGRYQCLAT 79


                  ....*...
gi 281360617  115 NEFGTATS 122
Cdd:cd05848    80 NSIGSILS 87

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 57.73 E-value: 3.73e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  341 FTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDNTIRIINLVKG-DTGNYGCNATNSLGYV 419
Cdd:cd20949     2 FTENAYVTTVKEGQSATILCEVKGEPQPNVTWHFNGQPISASVADMSKYRILADGLLINKVTQdDTGEYTCRAYQVNSIA 81


                  ....*...
gi 281360617  420 YKDVYLNV 427
Cdd:cd20949    82 SDMQERTV 89

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 57.12 E-value: 5.41e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  434 ISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGG--RYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQA 511
Cdd:cd20952     2 ILQGPQNQTVAVGGTVVLNCQATGEPVPTISWLKDGVPLLGKdeRITTLENGSLQIKGAEKSDTGEYTCVALNLSGEATW 81


                  ....*.
gi 281360617  512 DGSLVV 517
Cdd:cd20952    82 SAVLDV 87

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 57.07 E-value: 5.91e-10

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617   55 FIIECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQpgRGTLVITIPKDEDRGHYQCFASNEFGTATSNsVYV 127
Cdd:cd04978    17 GELICEAEGNPQPTITWRLNGVPIEPAPEDMRRTVD--GRTLIFSNLQPNDTAVYQCNASNVHGYLLAN-AFL 86

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 56.84 E-value: 6.09e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  433 TISEAPAAVstvdGRNVTIKCRVNGSPKPLVKWLRASNWL-TGGRYNVQaNGDLEIQDVTFSDAGKYTCYAQNKFGEIQA 511
Cdd:cd05728     5 VISDTEADI----GSSLRWECKASGNPRPAYRWLKNGQPLaSENRIEVE-AGDLRITKLSLSDSGMYQCVAENKHGTIYA 79


                  ....*.
gi 281360617  512 DGSLVV 517
Cdd:cd05728    80 SAELAV 85

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 57.03 E-value: 6.13e-10

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617   54 PFIIECEAD-GQPEPEYSWIKNGKKFDwqaYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNSVYV 127
Cdd:cd05724    14 MAVLECSPPrGHPEPTVSWRKDGQPLN---LDNERVRIVDDGNLLIAEARKSDEGTYKCVATNMVGERESRAARL 85

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 56.80 E-value: 6.21e-10

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617   522 RITQEPQNYEVAAGQSATFRCNEAHDDTLEIEidWWKDGQSIDFEAQPRFVKTNDNS-LTIAKTMELDSGEYTCVAR 597
Cdd:pfam13927    3 VITVSPSSVTVREGETVTLTCEATGSPPPTIT--WYKNGEPISSGSTRSRSLSGSNStLTISNVTRSDAGTYTCVAS 77

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 56.74 E-value: 6.70e-10

                            10        20        30        40        50        60        70
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617    257 LALRGKRMELFCIYGGTPLPQTVWSKDGQR-IQWSDR--ITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQS 328
Cdd:smart00410    5 TVKEGESVTLSCEASGSPPPEVTWYKQGGKlLAESGRfsVSRSGSTSTLTISNVTPEDSGTYTCAATNSSGSASS 79

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 57.21 E-value: 6.84e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQStpnPRRTVTDN----TIRIINLVKGDTGNYGCNATN 414
Cdd:cd20972     2 PQFIQKLRSQEVAEGSKVRLECRVTGNPTPVVRWFCEGKELQNS---PDIQIHQEgdlhSLIIAEAFEEDTGRYSCLATN 78


                  ...
gi 281360617  415 SLG 417
Cdd:cd20972    79 SVG 81

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 57.12 E-value: 7.12e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGG----RYnVQANG--DLEIQDVTFSDAGKYTCYAQNK 505
Cdd:cd05744     1 PHFLQAPGDLEVQEGRLCRFDCKVSGLPTPDLFWQLNGKPVRPDsahkML-VRENGrhSLIIEPVTKRDAGIYTCIARNR 79

                          90
                  ....*....|..
gi 281360617  506 FGEIQADGSLVV 517
Cdd:cd05744    80 AGENSFNAELVV 91

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 56.87 E-value: 8.03e-10

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLGY 418
Cdd:cd20976     2 PSFSSVPKDLEAVEGQDFVAQCSARGKPVPRITWIRNAQPLQYAADRSTCEAGVGELHIQDVLPEDHGTYTCLAKNAAGQ 81


                  ....*....
gi 281360617  419 VYKDVYLNV 427
Cdd:cd20976    82 VSCSAWVTV 90

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 56.26 E-value: 9.27e-10

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281360617  349 TAAEDEEVVFECRAAGVPEPKISWIhngkPIEQSTPnPRRTVTDN---TIRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd05731     6 MVLRGGVLLLECIAEGLPTPDIRWI----KLGGELP-KGRTKFENfnkTLKIENVSEADSGEYQCTASNTMG 72

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 56.49 E-value: 1.05e-09

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617   54 PFIIECEADGQPEPEYSWIKNGKkfDWQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTAT 121
Cdd:cd20976    18 DFVAQCSARGKPVPRITWIRNAQ--PLQYAADRSTCEAGVGELHIQDVLPEDHGTYTCLAKNAAGQVS 83

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 55.97 E-value: 1.70e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  613 DVPNAPKLTGITcqADKAEIHWEQQGDNRSPILHYTIQFNTSFTPASwdAAYEKVPNTDSSFVVQ-MSPWANYTFRVIAF 691
Cdd:cd00063     2 SPPTNLRVTDVT--STSVTLSWTPPEDDGGPITGYVVEYREKGSGDW--KEVEVTPGSETSYTLTgLKPGTEYEFRVRAV 77

                          90
                  ....*....|....*.
gi 281360617  692 NKIGASPPSAHSDSCT 707
Cdd:cd00063    78 NGGGESPPSESVTVTT 93

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 55.68 E-value: 1.78e-09

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617   58 ECEADGQPEPEYSWIKNGKKFdwqAYDNRMlrQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNS 124
Cdd:cd05728    20 ECKASGNPRPAYRWLKNGQPL---ASENRI--EVEAGDLRITKLSLSDSGMYQCVAENKHGTIYASA 81

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 55.73 E-value: 1.85e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLT---GGRYNVQANG-DLEIQDVTFSDAGKYTCYAQNKFG 507
Cdd:cd05736     1 PVIRVYPEFQAKEPGVEASLRCHAEGIPLPRVQWLKNGMDINpklSKQLTLIANGsELHISNVRYEDTGAYTCIAKNEGG 80

                          90
                  ....*....|..
gi 281360617  508 EIQADGSLVVKE 519
Cdd:cd05736    81 VDEDISSLFVED 92

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 55.47 E-value: 2.38e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  346 EIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTV-TDNTIRIINLVKGDTGNYGCNATNSLGYVYKDVY 424
Cdd:cd20969    10 QQVFVDEGHTVQFVCRADGDPPPAILWLSPRKHLVSAKSNGRLTVfPDGTLEVRYAQVQDNGTYLCIAANAGGNDSMPAH 89


                  ...
gi 281360617  425 LNV 427
Cdd:cd20969    90 LHV 92

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 55.20 E-value: 2.76e-09

                            10        20        30        40        50        60        70
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617     57 IECEADGQPEPEYSWIKNGKKfdWQAYDNR--MLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSN-SVYV 127
Cdd:smart00410   14 LSCEASGSPPPEVTWYKQGGK--LLAESGRfsVSRSGSTSTLTISNVTPEDSGTYTCAATNSSGSASSGtTLTV 85

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 55.64 E-value: 2.86e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   29 PRITKQPApgELLFKVAqqnkesdNPFIIECEADGQPEPEYSWIKNGKKFDWQAYD---NRMLRQPGRGTLVITIP---K 102
Cdd:cd07693     1 PRIVEHPS--DLIVSKG-------DPATLNCKAEGRPTPTIQWLKNGQPLETDKDDprsHRIVLPSGSLFFLRVVHgrkG 71

                          90       100
                  ....*....|....*....|
gi 281360617  103 DEDRGHYQCFASNEFGTATS 122
Cdd:cd07693    72 RSDEGVYVCVAHNSLGEAVS 91

Sixth immunoglobulin (Ig) domain of contactin-4; The members here are composed of the sixth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-4. Contactins are neural cell adhesion molecules, and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. Highest expression of contactin-4 is in testes, thyroid, small intestine, uterus, and brain. Contactin-4 plays a role in the response of neuroblastoma cells to differentiating agents, such as retinoids. The contactin 4 gene is associated with cerebellar degeneration in spinocerebellar ataxia type 16.

Pssm-ID: 409439 Cd Length: 102 Bit Score: 55.40 E-value: 3.29e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  521 TRITQEPQNYEVAAGQSATFRCNEAHDDTLEIEIDWWKDGQSIDFEAQPRF---VKTNDNS--LTIAKTMELDSGEYTCV 595
Cdd:cd05853     3 TRVMVPPSSMDVTVGESIVLPCQVSHDHSLDIVFTWSFNGHLIDFQKDGDHferVGGQDSAgdLMIRSIQLKHAGKYVCM 82

                          90       100
                  ....*....|....*....|
gi 281360617  596 ARTRLDEATARANLIVQDVP 615
Cdd:cd05853    83 VQTSVDKLSAAADLIVRGPP 102

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 54.87 E-value: 4.15e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPR--RTVTDNT----IRIINLVKG--DTGNYGC 410
Cdd:cd07693     1 PRIVEHPSDLIVSKGDPATLNCKAEGRPTPTIQWLKNGQPLETDKDDPRshRIVLPSGslffLRVVHGRKGrsDEGVYVC 80

                          90
                  ....*....|
gi 281360617  411 NATNSLGYVY 420
Cdd:cd07693    81 VAHNSLGEAV 90

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 54.94 E-value: 4.62e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  348 ATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLGYVYKDVYLNV 427
Cdd:cd05730    13 ATANLGQSVTLACDADGFPEPTMTWTKDGEPIESGEEKYSFNEDGSEMTILDVDKLDEAEYTCIAENKAGEQEAEIHLKV 92


                  ...
gi 281360617  428 QAE 430
Cdd:cd05730    93 FAK 95

Immunoglobulin (Ig)-like domain of human titin C terminus and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain from the C-terminus of human titin x and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is gigantic; depending on isoform composition it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone and appears to function similar to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 143224 [Multi-domain] Cd Length: 92 Bit Score: 54.67 E-value: 4.65e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWL-TGGRYNV---QANGDLEIQDVTFSDAGKYTCYAQNKF 506
Cdd:cd05747     3 PATILTKPRSLTVSEGESARFSCDVDGEPAPTVTWMREGQIIvSSQRHQItstEYKSTFEISKVQMSDEGNYTVVVENSE 82


                  ....*....
gi 281360617  507 GEIQADGSL 515
Cdd:cd05747    83 GKQEAQFTL 91

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 54.11 E-value: 4.84e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617   251 VSRRQSLALRGKRMELFCIYGGTPLPQTVWSKDGQRI--QWSDRITQGHYGKSLVIRQTNFDDAGTYTCDVSN 321
Cdd:pfam13927    6 VSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPIssGSTRSRSLSGSNSTLTISNVTRSDAGTYTCVASN 78

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 54.42 E-value: 4.96e-09

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617   58 ECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNsvyvrkAELN 133
Cdd:cd05744    21 DCKVSGLPTPDLFWQLNGKPVRPDSAHKMLVRENGRHSLIIEPVTKRDAGIYTCIARNRAGENSFN------AELV 90

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 53.95 E-value: 5.70e-09

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617  257 LALRGKRMELFCIYGGTPLPQTVWSKDGQRIQwSDRITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQ-SFSII 332
Cdd:cd05731     6 MVLRGGVLLLECIAEGLPTPDIRWIKLGGELP-KGRTKFENFNKTLKIENVSEADSGEYQCTASNTMGSARhTISVT 81

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 54.02 E-value: 6.73e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTG--GRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEI 509
Cdd:cd05764     1 PLITRHTHELRVLEGQRATLRCKARGDPEPAIHWISPEGKLISnsSRTLVYDNGTLDILITTVKDTGAFTCIASNPAGEA 80


                  ....*...
gi 281360617  510 QADGSLVV 517
Cdd:cd05764    81 TARVELHI 88

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 54.13 E-value: 6.83e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  245 PPvrQYVSRRQSLALR-GKRMELFCIYGGTPLPQTVWSKDGQRIQWSD--RITQGHYGKSLVIRQTNFDDAGTYTCDVSN 321
Cdd:cd20972     1 PP--QFIQKLRSQEVAeGSKVRLECRVTGNPTPVVRWFCEGKELQNSPdiQIHQEGDLHSLIIAEAFEEDTGRYSCLATN 78

                          90
                  ....*....|..
gi 281360617  322 GVGNAQSFSIIL 333
Cdd:cd20972    79 SVGSDTTSAEIF 90

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 53.94 E-value: 6.93e-09

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617  343 KEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIeqstPNPR-RTVTDNTIRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd05725     2 KRPQNQVVLVDDSAEFQCEVGGDPVPTVRWRKEDGEL----PKGRyEILDDHSLKIRKVTAGDMGSYTCVAENMVG 73

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 53.34 E-value: 7.30e-09

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  449 VTIKCRVNGSPKPLVKWLRASNWLT-GGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFG 507
Cdd:cd05746     1 VQIPCSAQGDPEPTITWNKDGVQVTeSGKFHISPEGYLAIRDVGVADQGRYECVARNTIG 60

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 54.19 E-value: 7.33e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  446 GRNVTIKCRVNGSPKPLVKWLR--ASNWL-------TGGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSLV 516
Cdd:cd05726    14 GRTVTFQCETKGNPQPAIFWQKegSQNLLfpyqppqPSSRFSVSPTGDLTITNVQRSDVGYYICQALNVAGSILAKAQLE 93


                  ...
gi 281360617  517 VKE 519
Cdd:cd05726    94 VTD 96

Third immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The third Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules, including vascular (VCAM), intercellular (ICAM), neural (NCAM) and mucosal addressin (MADCAM) cell adhesion molecules, as well as junction adhesion molecules (JAM).

Pssm-ID: 409569 Cd Length: 93 Bit Score: 54.32 E-value: 7.58e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  246 PVRQYVSRRQsLALRGKRMELFCIYGGTPLPQTVWSKDGQRIQWS--DRITQ--GHYGKSLVIRQTNFDDAGTYTCDVSN 321
Cdd:cd20977     1 PVPQYVSKDM-MAKAGDVTMIYCMYGSNPTAHPNYFKNGKDVNGNpeDRITRhnRTSGKRLLFKTTLPEDEGVYTCEVDN 79

                          90
                  ....*....|....
gi 281360617  322 GVGNAQSFSIILNV 335
Cdd:cd20977    80 GVGKPQKHSLKLTV 93

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 54.00 E-value: 7.78e-09

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617   56 IIECEADGQPEPEYSWIKNGKkfdwqaydnrMLRQPGR------GTLVITIPKDEDRGHYQCFASNEFGTATS 122
Cdd:cd04969    21 IIECKPKASPKPTISWSKGTE----------LLTNSSRicilpdGSLKIKNVTKSDEGKYTCFAVNFFGKANS 83

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 59.63 E-value: 8.68e-09

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  653 TSFTPASWDAAYEKVPNTDSSFVVQMSPWANYTFRVIAFNKIGASPPSahSDSCTTQPDVPFKNPDNVVGQGTEPNNLVI 732
Cdd:COG3401   174 TSATAAVATTSLTVTSTTLVDGGGDIEPGTTYYYRVAATDTGGESAPS--NEVSVTTPTTPPSAPTGLTATADTPGSVTL 251

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  733 SWTPmpeieHNAPNFHYYVSWKRDIPAAAWE-----NNNIFdwrQNNIVIADQptfvKYLIKVVAINDRGESNVAAEEVV 807
Cdd:COG3401   252 SWDP-----VTESDATGYRVYRSNSGDGPFTkvatvTTTSY---TDTGLTNGT----TYYYRVTAVDAAGNESAPSNVVS 319

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  808 GYSGEDRPlDAPTNFTmrqITSSTSG--YMAWTPVSEESVrghfKGYKIQTWTENEGEegLREIHVKGDTHNALVTQFKP 885
Cdd:COG3401   320 VTTDLTPP-AAPSGLT---ATAVGSSsiTLSWTASSDADV----TGYNVYRSTSGGGT--YTKIAETVTTTSYTDTGLTP 389

                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  886 DSKNYARILAYNGRFNGPPSAVIDFDTPEGVPSPVQGLDAYPLGSSAFMLHWKKPLYPNGKLTGYKIYYeevkesYVGER 965
Cdd:COG3401   390 GTTYYYKVTAVDAAGNESAPSEEVSATTASAASGESLTASVDAVPLTDVAGATAAASAASNPGVSAAVL------ADGGD 463

                         330       340       350       360
                  ....*....|....*....|....*....|....*....|....*...
gi 281360617  966 REYDPHITDPRVTRMKMAGLKPNSKYRISITATTKMGEGSEHYIEKTT 1013
Cdd:COG3401   464 TGNAVPFTTTSSTVTATTTDTTTANLSVTTGSLVGGSGASSVTNSVSV 511

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 53.57 E-value: 1.08e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   613 DVPNAPKLTGITcqADKAEIHWEQQGDNRSPILHYTIQFNTSFTPASWdaAYEKVPNTDSSFVVQ-MSPWANYTFRVIAF 691
Cdd:pfam00041    1 SAPSNLTVTDVT--STSLTVSWTPPPDGNGPITGYEVEYRPKNSGEPW--NEITVPGTTTSVTLTgLKPGTEYEVRVQAV 76


                   ....*....
gi 281360617   692 NKIGASPPS 700
Cdd:pfam00041   77 NGGGEGPPS 85

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 53.35 E-value: 1.14e-08

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  444 VDGRNVTIKCRVNGSPKPLVKWLRASNWLTGGR-----YNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSLVV 517
Cdd:cd20973    10 VEGSAARFDCKVEGYPDPEVKWMKDDNPIVESRrfqidQDEDGLCSLIISDVCGDDSGKYTCKAVNSLGEATCSAELTV 88

Fourth immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues, and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409388 Cd Length: 84 Bit Score: 52.97 E-value: 1.35e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  343 KEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQStpNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLGyvykd 422
Cdd:cd05723     2 KKPSNIYAHESMDIVFECEVTGKPTPTVKWVKNGDVVIPS--DYFKIVKEHNLQVLGLVKSDEGFYQCIAENDVG----- 74


                  ....*..
gi 281360617  423 vylNVQA 429
Cdd:cd05723    75 ---NAQA 78

Second immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins. L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region, and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1 that involves abnormalities of axonal growth. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409432 Cd Length: 91 Bit Score: 53.26 E-value: 1.46e-08

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617  138 EAAKTLEAVEGEPFMLKCAAPDGFPSPTVNWMiqesiDGSIKSI-NNSRMTLDPEGNLWFSNVTREDASSDfyYACSA 214
Cdd:cd05845     2 EKIDPVEVEEGDPVVLPCNPPKGAPPPRIYWM-----NSSLEHItQDERVSMGQNGDLYFSNVMEQDSHPD--YICHA 72

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 52.81 E-value: 1.99e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDN----TIRIINLVKGDTGNYGCNATN 414
Cdd:cd20951     1 PEFIIRLQSHTVWEKSDAKLRVEVQGKPDPEVKWYKNGVPIDPSSIPGKYKIESEygvhVLHIRRVTVEDSAVYSAVAKN 80

                          90
                  ....*....|....
gi 281360617  415 SLGYVYKDVYLNVQ 428
Cdd:cd20951    81 IHGEASSSASVVVE 94

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 53.01 E-value: 2.13e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEAPAAV-STVD-GRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQANGD---LEIQDVTFSDAGKYTCYAQNK 505
Cdd:cd05730     1 PPTIRARQSEVnATANlGQSVTLACDADGFPEPTMTWTKDGEPIESGEEKYSFNEDgseMTILDVDKLDEAEYTCIAENK 80

                          90
                  ....*....|..
gi 281360617  506 FGEIQADGSLVV 517
Cdd:cd05730    81 AGEQEAEIHLKV 92

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 52.64 E-value: 2.30e-08

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617    58 ECEADGQPEPEYSWIKNGKKF-DWQAYdnRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATS 122
Cdd:pfam07679   21 TCTVTGTPDPEVSWFKDGQPLrSSDRF--KVTYEGGTYTLTISNVQPDDSGKYTCVATNSAGEAEA 84

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 52.40 E-value: 2.43e-08

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  525 QEPQNYEVAAGQSATFRCN--EAHDdtlEIEIDWWKDGQSIDfEAQPRFVKTNDNSLTIAKTMELDSGEYTCVA 596
Cdd:cd05724     2 VEPSDTQVAVGEMAVLECSppRGHP---EPTVSWRKDGQPLN-LDNERVRIVDDGNLLIAEARKSDEGTYKCVA 71

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 52.63 E-value: 2.43e-08

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617   57 IECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQpgrGTLVITIP-KDEDRGHYQCFASNEFGTATS 122
Cdd:cd04967    24 LNCRARANPVPSYRWLMNGTEIDLESDYRYSLVD---GTLVISNPsKAKDAGHYQCLATNTVGSVLS 87

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 52.33 E-value: 2.60e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  433 TISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGG-----RYNVQANGdLEIQDVTFSDAGKYTCYAQNKFG 507
Cdd:cd20949     1 TFTENAYVTTVKEGQSATILCEVKGEPQPNVTWHFNGQPISASvadmsKYRILADG-LLINKVTQDDTGEYTCRAYQVNS 79

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 52.58 E-value: 2.61e-08

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  261 GKRMELFCIYGGTPLPQTVWSKDGQRIQWSDRIT---QGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNA 326
Cdd:cd20973    12 GSAARFDCKVEGYPDPEVKWMKDDNPIVESRRFQidqDEDGLCSLIISDVCGDDSGKYTCKAVNSLGEA 80

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 52.24 E-value: 3.38e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  342 TKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQstpNPRRTVTDN-TIRIINLVKGDTGNYGCNATNSLGYVY 420
Cdd:cd20968     3 TRPPTNVTIIEGLKAVLPCTTMGNPKPSVSWIKGDDLIKE---NNRIAVLESgSLRIHNVQKEDAGQYRCVAKNSLGIAY 79


                  ....*....
gi 281360617  421 -KDVYLNVQ 428
Cdd:cd20968    80 sKPVTIEVE 88

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 52.25 E-value: 3.51e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPE---IATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTpNPRRTVTDNTIRIINLVKG-DTGNYGCNATN 414
Cdd:cd05848     2 PVFVQEPDdaiFPTDSDEKKVILNCEARGNPVPTYRWLRNGTEIDTES-DYRYSLIDGNLIISNPSEVkDSGRYQCLATN 80


                  ....*
gi 281360617  415 SLGYV 419
Cdd:cd05848    81 SIGSI 85

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 52.10 E-value: 4.01e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  340 YFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDNTIRIINLV-----KGDTGNYGCNATN 414
Cdd:cd05722     3 YFLSEPSDIVAMRGGPVVLNCSAESDPPPKIEWKKDGVLLNLVSDERRQQLPNGSLLITSVVhskhnKPDEGFYQCVAQN 82


                  ....*.
gi 281360617  415 -SLGYV 419
Cdd:cd05722    83 eSLGSI 88

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 51.86 E-value: 4.27e-08

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617  434 ISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWL-TGGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFG 507
Cdd:cd20968     2 ITRPPTNVTIIEGLKAVLPCTTMGNPKPSVSWIKGDDLIkENNRIAVLESGSLRIHNVQKEDAGQYRCVAKNSLG 76

Second immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains.

Pssm-ID: 409400 [Multi-domain] Cd Length: 91 Bit Score: 51.94 E-value: 4.83e-08

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   50 ESDNPFIIECEADGQPEPEYSWIKNGKKFDWQAYDNRmLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATS--NSVYV 127
Cdd:cd05738    12 EKARTATMLCAASGNPDPEISWFKDFLPVDTATSNGR-IKQLRSGALQIENSEESDQGKYECVATNSAGTRYSapANLYV 90


                  .
gi 281360617  128 R 128
Cdd:cd05738    91 R 91

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 51.25 E-value: 6.27e-08

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617  141 KTLEAVEGEPFMLKCAAPDGFPSPTVNWMiqesIDGSIKSINNSRMTLDPEGNLWFSNVTREDASSdfyYACSATSV 217
Cdd:cd05724     5 SDTQVAVGEMAVLECSPPRGHPEPTVSWR----KDGQPLNLDNERVRIVDDGNLLIAEARKSDEGT---YKCVATNM 74

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 50.71 E-value: 7.58e-08

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617  352 EDEEVVFECRAAGVPEPKISWIHNGKPIeqstPNPRRTV--TDNTIRIINLVKGDTGNYGCNATNSLGYVYKDVYLNV 427
Cdd:cd05745     1 EGQTVDFLCEAQGYPQPVIAWTKGGSQL----SVDRRHLvlSSGTLRISRVALHDQGQYECQAVNIVGSQRTVAQLTV 74

Second immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains.

Pssm-ID: 409400 [Multi-domain] Cd Length: 91 Bit Score: 50.78 E-value: 1.09e-07

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281360617  360 CRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDN-TIRIINLVKGDTGNYGCNATNSLGYVY 420
Cdd:cd05738    21 CAASGNPDPEISWFKDFLPVDTATSNGRIKQLRSgALQIENSEESDQGKYECVATNSAGTRY 82

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 50.47 E-value: 1.27e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  258 ALRGKRMELFCIYGGTPLPQTVWSKDGQRI------QWSDritqghygKSLVIRQTNFDDAGTYTCDVSNGVGNAQSfSI 331
Cdd:cd05725     9 VLVDDSAEFQCEVGGDPVPTVRWRKEDGELpkgryeILDD--------HSLKIRKVTAGDMGSYTCVAENMVGKIEA-SA 79


                  ....
gi 281360617  332 ILNV 335
Cdd:cd05725    80 TLTV 83

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 50.29 E-value: 1.34e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  358 FECRAAGVPEPKISWIHNGKPIEQSTpnpRRTVTDNTIRIINLVKGDTGNYGCNATNSLGYVYKDVYLNV 427
Cdd:cd05728    19 WECKASGNPRPAYRWLKNGQPLASEN---RIEVEAGDLRITKLSLSDSGMYQCVAENKHGTIYASAELAV 85

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 50.27 E-value: 1.75e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  524 TQEPQNYEVAAGQSATFRCN-EAHDDTleiEIDWWKDGQSIDFEAQPRFVKTNDN--SLTIAKTMELDSGEYTCVARTRL 600
Cdd:cd20973     1 IQTLRDKEVVEGSAARFDCKvEGYPDP---EVKWMKDDNPIVESRRFQIDQDEDGlcSLIISDVCGDDSGKYTCKAVNSL 77

                          90
                  ....*....|.
gi 281360617  601 DEATARANLIV 611
Cdd:cd20973    78 GEATCSAELTV 88

Third immunoglobulin (Ig)-like domain of fibroblast growth factor receptor 2 (FGFR2); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain of human fibroblast growth factor receptor 2 (FGFR2). Fibroblast growth factors (FGFs) participate in morphogenesis, development, angiogenesis, and wound healing. These FGF-stimulated processes are mediated by four FGFR tyrosine kinases (FGRF1-4). FGFRs are comprised of an extracellular portion consisting of three Ig-like domains, a transmembrane helix, and a cytoplasmic portion having protein tyrosine kinase activity. The highly conserved Ig-like domains 2 and 3, and the linker region between D2 and D3 define a general binding site for FGFs. FGFR2 is required for male sex determination. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409444 Cd Length: 105 Bit Score: 50.73 E-value: 1.84e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  438 PAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNwLTGGRYN---------VQANG------DLEI---QDVTFSDAGKYT 499
Cdd:cd05858     8 PANTSVVVGTDAEFVCKVYSDAQPHIQWLKHVE-KNGSKYGpdglpyvevLKTAGvnttdkEIEVlylRNVTFEDAGEYT 86


                  ....*...
gi 281360617  500 CYAQNKFG 507
Cdd:cd05858    87 CLAGNSIG 94

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 49.91 E-value: 1.85e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  446 GRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQA-NGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSLVVK 518
Cdd:cd05876    10 GQSLVLECIAEGLPTPTVKWLRPSGPLPPDRVKYQNhNKTLQLLNVGESDDGEYVCLAENSLGSARHAYYVTVE 83

Fourth immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues, and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409388 Cd Length: 84 Bit Score: 49.89 E-value: 1.86e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  438 PAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGGRY-NVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSLV 516
Cdd:cd05723     4 PSNIYAHESMDIVFECEVTGKPTPTVKWVKNGDVVIPSDYfKIVKEHNLQVLGLVKSDEGFYQCIAENDVGNAQASAQLI 83


                  .
gi 281360617  517 V 517
Cdd:cd05723    84 I 84

Immunoglobulin (Ig)-like domain found in neuregulin (NRG)-1; The members here are composed of the immunoglobulin (Ig)-like domain found in neuregulin (NRG)-1. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. NRG-1 belongs to the neuregulin gene family which is comprised of four genes. This group represents NRG-1. NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, and heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. The NRG-1 protein binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. NRG-1 has multiple functions, for example, in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival.

Pssm-ID: 409476 Cd Length: 93 Bit Score: 49.99 E-value: 2.29e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  525 QEPQNYEVAAGQSATFRCnEAHDDTLEIEIDWWKDGQSIDFEAQPRFVKT----NDNSLTIAKTMELDSGEYTCVARTRL 600
Cdd:cd05895     4 KEMKSQEVAAGSKLVLRC-ETSSEYPSLRFKWFKNGKEINRKNKPENIKIqkkkKKSELRINKASLADSGEYMCKVSSKL 82

                          90
                  ....*....|.
gi 281360617  601 DEATARANLIV 611
Cdd:cd05895    83 GNDSASANVTI 93

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 49.33 E-value: 2.38e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617   52 DNPFIIECEADGQPEPEYSWIKNGKKFdwqaYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSN-SVYVR 128
Cdd:cd05731    10 GGVLLLECIAEGLPTPDIRWIKLGGEL----PKGRTKFENFNKTLKIENVSEADSGEYQCTASNTMGSARHTiSVTVE 83

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 49.89 E-value: 2.38e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   28 PPRITKQPAPGEllfkVAQQNKesdnpFIIECEADGQPEPEYSWIKNGKKFDwQAYDNRMLRQPGRGTLVITIPKDEDRG 107
Cdd:cd20972     1 PPQFIQKLRSQE----VAEGSK-----VRLECRVTGNPTPVVRWFCEGKELQ-NSPDIQIHQEGDLHSLIIAEAFEEDTG 70

                          90
                  ....*....|....*..
gi 281360617  108 HYQCFASNEFGTATSNS 124
Cdd:cd20972    71 RYSCLATNSVGSDTTSA 87

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 49.53 E-value: 3.22e-07

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617   57 IECEADGQPEPEYSWIKNGKKFdWQAYDNRMLRQPGRG-TLVITIPKDEDRGHYQCFASNEFGT 119
Cdd:cd05729    24 LECGAGGNPMPNITWLKDGKEF-KKEHRIGGTKVEEKGwSLIIERAIPRDKGKYTCIVENEYGS 86

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 49.43 E-value: 3.29e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  258 ALRGKRMELFCIYGGTPLPQTVWSKDGQRIQwsdRITQGH----YGKSLVIRQTNFDDAGTYTCDVSNGVGNAQSFSIIL 333
Cdd:cd20970    14 AREGENATFMCRAEGSPEPEISWTRNGNLII---EFNTRYivreNGTTLTIRNIRRSDMGIYLCIASNGVPGSVEKRITL 90


                  ..
gi 281360617  334 NV 335
Cdd:cd20970    91 QV 92

Immunoglobulin-like domain of human Aortic Preferentially Expressed Protein-1 (APEG-1) and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin I-set (IgI) domain of the Human Aortic Preferentially Expressed Protein-1 (APEG-1) and similar proteins. APEG-1 is a novel specific smooth muscle differentiation marker predicted to play a role in the growth and differentiation of arterial smooth muscle cells (SMCs). The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the human APEG-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409567 Cd Length: 91 Bit Score: 49.39 E-value: 3.31e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQANGD-----LEIQDVTFSDAGKYTCYAQNKF 506
Cdd:cd20975     1 PTFKVSLMDQSVREGQDVIMSIRVQGEPKPVVSWLRNRQPVRPDQRRFAEEAEgglcrLRILAAERGDAGFYTCKAVNEY 80

                          90
                  ....*....|.
gi 281360617  507 GEIQADGSLVV 517
Cdd:cd20975    81 GARQCEARLEV 91

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 49.62 E-value: 3.37e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   28 PPRITKQPApgellfkvaQQNKESDNPFIIECEADGQPEPEYSWIKN-----GKKFDWqAYDNRmLRQPGRGTLVITIPK 102
Cdd:cd20954     1 PPRWIVEPV---------DANVAAGQDVMLHCQADGFPTPTVTWKKAtgstpGEYKDL-LYDPN-VRILPNGTLVFGHVQ 69

                          90       100
                  ....*....|....*....|....*
gi 281360617  103 DEDRGHYQCFASNEFGTATSNSVYV 127
Cdd:cd20954    70 KENEGHYLCEAKNGIGSGLSKVIFL 94

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 49.16 E-value: 3.71e-07

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617   57 IECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNS 124
Cdd:cd05763    19 LECAATGHPTPQIAWQKDGGTDFPAARERRMHVMPEDDVFFIVDVKIEDTGVYSCTAQNSAGSISANA 86

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 48.93 E-value: 3.75e-07

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617   260 RGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDRitqghygksLVIRQTNFDDAGTYTCDVSNGVGNAQSFSIILNV 335
Cdd:pfam13895   13 EGEPVTLTCSAPGNPPPSYTWYKDGSAISSSPN---------FFTLSVSAEDSGTYTCVARNGRGGKVSNPVELTV 79

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 49.17 E-value: 3.91e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  258 ALRGKRMELFCIYGGTPLPQTVWSKDGQRIQW-SDRITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNA 326
Cdd:cd20976    13 AVEGQDFVAQCSARGKPVPRITWIRNAQPLQYaADRSTCEAGVGELHIQDVLPEDHGTYTCLAKNAAGQV 82

C-terminal immunoglobulin (Ig)-like domain of M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of M-protein (also known as myomesin-2). M-protein is a structural protein localized to the M-band, a transverse structure in the center of the sarcomere, and is a candidate for M-band bridges. M-protein is modular consisting mainly of repetitive IG-like and fibronectin type III (FnIII) domains and has a muscle-type specific expression pattern. M-protein is present in fast fibers.

Pssm-ID: 143299 Cd Length: 92 Bit Score: 49.14 E-value: 4.55e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617  438 PAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLT-GGRYNVQAN----GDLEIQDVTFSDAGKYTCYAQNKFG 507
Cdd:cd05891     8 PDVVTIMEGKTLNLTCTVFGNPDPEVIWFKNDQDIElSEHYSVKLEqgkyASLTIKGVTSEDSGKYSINVKNKYG 82

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 48.48 E-value: 4.74e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  538 ATFRCnEAHDDTlEIEIDWWKDGQSIDFEAQ-PRFVKTNDNSLTIAKTMELDSGEYTCVARTRLDEATAR 606
Cdd:cd00096     1 VTLTC-SASGNP-PPTITWYKNGKPLPPSSRdSRRSELGNGTLTISNVTLEDSGTYTCVASNSAGGSASA 68

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 49.14 E-value: 5.20e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFT-----KEPEIATAAeDEEVVFECRAAGVPEPKISWIHNGKPIEqstPNPRRTVTDN-----TIRIINLVKGDTGNY 408
Cdd:cd05729     1 PRFTdtekmEEREHALPA-ANKVRLECGAGGNPMPNITWLKDGKEFK---KEHRIGGTKVeekgwSLIIERAIPRDKGKY 76


                  ....*....
gi 281360617  409 GCNATNSLG 417
Cdd:cd05729    77 TCIVENEYG 85

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 48.73 E-value: 5.26e-07

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617   445 DGRNVTIKCRVN-GSPKPLVKWLRASNWLTGGRYNVQANGD-----LEIQDVTFSDAGKYTCYAQNKFGEIQA 511
Cdd:pfam00047   10 EGDSATLTCSAStGSPGPDVTWSKEGGTLIESLKVKHDNGRttqssLLISNVTKEDAGTYTCVVNNPGGSATL 82

C-terminal immunoglobulin (Ig)-like domain of M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of M-protein (also known as myomesin-2). M-protein is a structural protein localized to the M-band, a transverse structure in the center of the sarcomere, and is a candidate for M-band bridges. M-protein is modular consisting mainly of repetitive IG-like and fibronectin type III (FnIII) domains and has a muscle-type specific expression pattern. M-protein is present in fast fibers.

Pssm-ID: 143299 Cd Length: 92 Bit Score: 48.75 E-value: 5.87e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  259 LRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSD----RITQGHYGkSLVIRQTNFDDAGTYTCDVSNGVGnAQSFSIILN 334
Cdd:cd05891    14 MEGKTLNLTCTVFGNPDPEVIWFKNDQDIELSEhysvKLEQGKYA-SLTIKGVTSEDSGKYSINVKNKYG-GETVDVTVS 91


                  .
gi 281360617  335 V 335
Cdd:cd05891    92 V 92

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 48.37 E-value: 6.05e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  350 AAEDEEVVFECRAAGVPEPKISWIHNGKPIEqstpnPRRTVTDN---TIRIINLVKGDTGNYGCNATNSLGYVYKDVYLN 426
Cdd:cd05876     7 ALRGQSLVLECIAEGLPTPTVKWLRPSGPLP-----PDRVKYQNhnkTLQLLNVGESDDGEYVCLAENSLGSARHAYYVT 81


                  ..
gi 281360617  427 VQ 428
Cdd:cd05876    82 VE 83

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 48.25 E-value: 6.14e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281360617  354 EEVVFECRAAGVPEPKISWIHNGKPIeqstPNPRRTVTDN-----TIRIINLVKGDTGNYGCNATNSLGYVY 420
Cdd:cd05743     2 ETVEFTCVATGVPTPIINWRLNWGHV----PDSARVSITSeggygTLTIRDVKESDQGAYTCEAINTRGMVF 69

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 48.85 E-value: 6.16e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNwLTGGRY---------NVQANGDLEIQDVTFSDAGKYTCY 501
Cdd:cd20954     1 PPRWIVEPVDANVAAGQDVMLHCQADGFPTPTVTWKKATG-STPGEYkdllydpnvRILPNGTLVFGHVQKENEGHYLCE 79


                  ....*.
gi 281360617  502 AQNKFG 507
Cdd:cd20954    80 AKNGIG 85

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 48.54 E-value: 6.27e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEAPAAVSTVD-GRNVTIKCRVNGSPKPLVKWLRASNWL----TGGRYNVQANGDLEIQDVTFSDAGKYTCYAQNK 505
Cdd:cd20969     1 RAAIRDRKAQQVFVDeGHTVQFVCRADGDPPPAILWLSPRKHLvsakSNGRLTVFPDGTLEVRYAQVQDNGTYLCIAANA 80

                          90
                  ....*....|..
gi 281360617  506 FGEIQADGSLVV 517
Cdd:cd20969    81 GGNDSMPAHLHV 92

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 48.01 E-value: 7.20e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  445 DGRNVTIKCRVNGSPKPLVKWLRASNWLT-GGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSLVV 517
Cdd:cd05745     1 EGQTVDFLCEAQGYPQPVIAWTKGGSQLSvDRRHLVLSSGTLRISRVALHDQGQYECQAVNIVGSQRTVAQLTV 74

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 48.57 E-value: 7.79e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617   58 ECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQP--GRGTLVITIPKDEDRGHYQCFASNEFGTATSN-SVYVR 128
Cdd:cd20951    21 RVEVQGKPDPEVKWYKNGVPIDPSSIPGKYKIESeyGVHVLHIRRVTVEDSAVYSAVAKNIHGEASSSaSVVVE 94

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 48.35 E-value: 7.92e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGG-RYNVQANGDLE---IQDVTFSDAGKYTCYAQNKF 506
Cdd:cd20972     1 PPQFIQKLRSQEVAEGSKVRLECRVTGNPTPVVRWFCEGKELQNSpDIQIHQEGDLHsliIAEAFEEDTGRYSCLATNSV 80


                  .
gi 281360617  507 G 507
Cdd:cd20972    81 G 81

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 48.01 E-value: 8.99e-07

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281360617   56 IIECEADGQPEPEYSWIKNgkkfDWQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNSVYV 127
Cdd:cd20968    18 VLPCTTMGNPKPSVSWIKG----DDLIKENNRIAVLESGSLRIHNVQKEDAGQYRCVAKNSLGIAYSKPVTI 85

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 48.39 E-value: 9.61e-07

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPE---IATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQsTPNPRRTVTDNTIRIINLVKG-DTGNYGCNATN 414
Cdd:cd04967     2 PVFEEQPDdtiFPEDSDEKKVALNCRARANPVPSYRWLMNGTEIDL-ESDYRYSLVDGTLVISNPSKAkDAGHYQCLATN 80


                  ....*
gi 281360617  415 SLGYV 419
Cdd:cd04967    81 TVGSV 85

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 47.89 E-value: 1.08e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  525 QEPQNYEVAAGQSATFRCnEAHDDTLEIEIDWWKDGQSIDfEAQPRFVKTNDN----SLTIAKTMELDSGEYTCVARTRL 600
Cdd:cd05750     4 KEMKSQTVQEGSKLVLKC-EATSENPSPRYRWFKDGKELN-RKRPKNIKIRNKkknsELQINKAKLEDSGEYTCVVENIL 81

                          90
                  ....*....|.
gi 281360617  601 DEATARANLIV 611
Cdd:cd05750    82 GKDTVTGNVTV 92

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 47.50 E-value: 1.18e-06

                            10        20        30        40        50        60        70
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617    141 KTLEAVEGEPFMLKCAAPdGFPSPTVNWMIQesidGSIKSINNSRMTLDPEGN---LWFSNVTREDASSdfyYACSATS 216
Cdd:smart00410    2 PSVTVKEGESVTLSCEAS-GSPPPEVTWYKQ----GGKLLAESGRFSVSRSGStstLTISNVTPEDSGT---YTCAATN 72

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 47.86 E-value: 1.22e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  434 ISEaPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGG---RYNVQANGDLEIQDVTFS-----DAGKYTCYAQNK 505
Cdd:cd05722     5 LSE-PSDIVAMRGGPVVLNCSAESDPPPKIEWKKDGVLLNLVsdeRRQQLPNGSLLITSVVHSkhnkpDEGFYQCVAQNE 83


                  ....*
gi 281360617  506 -FGEI 509
Cdd:cd05722    84 sLGSI 88

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three IG-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans.

Pssm-ID: 409443 [Multi-domain] Cd Length: 95 Bit Score: 47.93 E-value: 1.24e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  446 GRNVTIKCRVNGSPKPLVKWLRASNWLTG----GRYNV-QANGDLEIQDVTFSDAGKYTCYAQNKFGEI 509
Cdd:cd05857    19 ANTVKFRCPAAGNPTPTMRWLKNGKEFKQehriGGYKVrNQHWSLIMESVVPSDKGNYTCVVENEYGSI 87

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 47.49 E-value: 1.34e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617   52 DNPFIIECEADGQPEPEYSWIKNGKKFDWQayDNRMLRQPgRGTLVITIPKDEDRGHYQCFASNEFGTATSNSV 125
Cdd:cd20952    14 GGTVVLNCQATGEPVPTISWLKDGVPLLGK--DERITTLE-NGSLQIKGAEKSDTGEYTCVALNLSGEATWSAV 84

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 2 (NCAM-2); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule NCAM-2 (also known as OCAM/mamFas II and RNCAM). NCAM-2 is organized similarly to NCAM, including five N-terminal Ig-like domains and two fibronectin type III domains. NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE), and may function like NCAM, as an adhesion molecule. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143278 [Multi-domain] Cd Length: 98 Bit Score: 47.66 E-value: 1.41e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  441 VSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLT--------GGRYNVQ---ANGDLEIQDVTFSDAGKYTCYAQNKFGEI 509
Cdd:cd05870    11 ETTVENGAATLSCKAEGEPIPEITWKRASDGHTfsegdkspDGRIEVKgqhGESSLHIKDVKLSDSGRYDCEAASRIGGH 90


                  .
gi 281360617  510 Q 510
Cdd:cd05870    91 Q 91

First immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409436 [Multi-domain] Cd Length: 95 Bit Score: 47.64 E-value: 1.49e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617  443 TVDGRnVTIKCRVNGSPKPLVKWlRASNW---LTGGRYNVqANGDLEIQDV-TFSDAGKYTCYAQNKFGEIQA 511
Cdd:cd05849    17 STEGK-VSVNCRARANPFPIYKW-RKNNLdidLTNDRYSM-VGGNLVINNPdKYKDAGRYVCIVSNIYGKVRS 86

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 47.51 E-value: 1.55e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   41 LFKVAQQNKESDNPFIIECEADG-QPEPEYSWIKNGKKFDWQAYDN-RMLRQPGRGTLVITIPKDEDRGHYQCFASNEFG 118
Cdd:cd05750     3 LKEMKSQTVQEGSKLVLKCEATSeNPSPRYRWFKDGKELNRKRPKNiKIRNKKKNSELQINKAKLEDSGEYTCVVENILG 82

                          90
                  ....*....|
gi 281360617  119 TATSN-SVYV 127
Cdd:cd05750    83 KDTVTgNVTV 92

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 47.45 E-value: 1.62e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  245 PPVRQYVSRRQSLALRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDRITQGHYGkSLVIRQTNFDDAGTYTCDVSNGVG 324
Cdd:cd04969     1 PDFELNPVKKKILAAKGGDVIIECKPKASPKPTISWSKGTELLTNSSRICILPDG-SLKIKNVTKSDEGKYTCFAVNFFG 79

                          90
                  ....*....|.
gi 281360617  325 NAQSfSIILNV 335
Cdd:cd04969    80 KANS-TGSLSV 89

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 47.18 E-value: 1.65e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  258 ALRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDRITQGHYGkSLVIRQTNFD-DAGTYTCDVSNGVGNAQSFSIILNV 335
Cdd:cd20958    12 AVAGQTLRLHCPVAGYPISSITWEKDGRRLPLNHRQRVFPNG-TLVIENVQRSsDEGEYTCTARNQQGQSASRSVFVKV 89

Third immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F (also known as LAR), type IIa; member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains. Included in this group is Drosophila LAR (DLAR).

Pssm-ID: 409401 Cd Length: 82 Bit Score: 47.20 E-value: 1.66e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEapaavsTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTG------GRyNVqangdLEIQDVTfsDAGKYTCYAQN 504
Cdd:cd05739     3 PPSNHE------VMPGGSVNLTCVAVGAPMPYVKWMKGGEELTKedempvGR-NV-----LELTNIY--ESANYTCVAIS 68

                          90
                  ....*....|....
gi 281360617  505 KFGEIQADGSLVVK 518
Cdd:cd05739    69 SLGMIEATAQVTVK 82

Immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains NrCAM [Ng(neuronglia)CAM-related cell adhesion molecule], which is primarily expressed in the nervous system, and human neurofascin. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409396 [Multi-domain] Cd Length: 94 Bit Score: 47.40 E-value: 1.88e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGR-NVTIKCRVNGSPKPLVKWLRAS---NWLTGGRYNVQAN-GDLEIQdvtFSDA------GKYTC 500
Cdd:cd05733     1 PTITEQSPKDYIVDPRdNITIKCEAKGNPQPTFRWTKDGkffDPAKDPRVSMRRRsGTLVID---NHNGgpedyqGEYQC 77


                  ....*..
gi 281360617  501 YAQNKFG 507
Cdd:cd05733    78 YASNELG 84

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 47.38 E-value: 2.06e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617   54 PFIIECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQPGrGTLVITIPKDEDRGHYQCFASNEFGTAT 121
Cdd:cd20969    19 TVQFVCRADGDPPPAILWLSPRKHLVSAKSNGRLTVFPD-GTLEVRYAQVQDNGTYLCIAANAGGNDS 85

Second C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409582 Cd Length: 91 Bit Score: 47.02 E-value: 2.30e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNpRRTVTDNTIR--IINLVKG-DTGNYGCNATNS 415
Cdd:cd20990     1 PHFLQAPGDLTVQEGKLCRMDCKVSGLPTPDLSWQLDGKPIRPDSAH-KMLVRENGVHslIIEPVTSrDAGIYTCIATNR 79


                  ..
gi 281360617  416 LG 417
Cdd:cd20990    80 AG 81

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 46.63 E-value: 2.47e-06

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617  272 GTPLPQTVWSKDGQRIQWSD-RITQGHYGKsLVIRQTNFDDAGTYTCDVSNGVGNAQS 328
Cdd:cd05724    24 GHPEPTVSWRKDGQPLNLDNeRVRIVDDGN-LLIAEARKSDEGTYKCVATNMVGERES 80

Immunoglobulin-like domain of human Aortic Preferentially Expressed Protein-1 (APEG-1) and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin I-set (IgI) domain of the Human Aortic Preferentially Expressed Protein-1 (APEG-1) and similar proteins. APEG-1 is a novel specific smooth muscle differentiation marker predicted to play a role in the growth and differentiation of arterial smooth muscle cells (SMCs). The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the human APEG-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409567 Cd Length: 91 Bit Score: 46.69 E-value: 2.81e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617  352 EDEEVVFECRAAGVPEPKISWIHNGKPIEqstPNPRRTVTDNT-----IRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd20975    14 EGQDVIMSIRVQGEPKPVVSWLRNRQPVR---PDQRRFAEEAEgglcrLRILAAERGDAGFYTCKAVNEYG 81

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 46.70 E-value: 3.07e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIH-NGKPIEQSTpnpRRTVTDN-TIRIINLVKGDTGNYGCNATNSL 416
Cdd:cd05764     1 PLITRHTHELRVLEGQRATLRCKARGDPEPAIHWISpEGKLISNSS---RTLVYDNgTLDILITTVKDTGAFTCIASNPA 77

                          90
                  ....*....|.
gi 281360617  417 GYVYKDVYLNV 427
Cdd:cd05764    78 GEATARVELHI 88

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 409395 [Multi-domain] Cd Length: 96 Bit Score: 46.75 E-value: 3.11e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  441 VSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLT------GGRYNVQAN---GDLEIQDVTFSDAGKYTCYAQNKFGEIQ 510
Cdd:cd05732    11 QTAVELEQITLTCEAEGDPIPEITWRRATRGISfeegdlDGRIVVRGHarvSSLTLKDVQLTDAGRYDCEASNRIGGDQ 89

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 46.72 E-value: 3.21e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  716 NPDNVVGQGTEPNNLVISWTPMPEIehNAPNFHYYVSWkRDIPAAAWENNNIFDWRQNNIVIADQPTFVKYLIKVVAIND 795
Cdd:cd00063     3 PPTNLRVTDVTSTSVTLSWTPPEDD--GGPITGYVVEY-REKGSGDWKEVEVTPGSETSYTLTGLKPGTEYEFRVRAVNG 79

                          90
                  ....*....|..
gi 281360617  796 RGESNVAAEEVV 807
Cdd:cd00063    80 GGESPPSESVTV 91

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 46.49 E-value: 3.25e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  345 PEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDNTIRIINLVK-GDTGNYGCNATNSLG 417
Cdd:cd05736     7 PEFQAKEPGVEASLRCHAEGIPLPRVQWLKNGMDINPKLSKQLTLIANGSELHISNVRyEDTGAYTCIAKNEGG 80

Immunoglobulin (Ig)-like domain of titin and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain found in titin-like proteins and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is a giant protein; depending on isoform composition, it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone. It appears to function similarly to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. Within the sarcomere, titin is also attached to or is associated with myosin binding protein C (MyBP-C). MyBP-C appears to contribute to the generation of passive tension by titin and like titin has repeated Ig-like and FN-III domains. Also included in this group are worm twitchin and insect projectin, thick filament proteins of invertebrate muscle which also have repeated Ig-like and FN-III domains.

Pssm-ID: 409406 [Multi-domain] Cd Length: 82 Bit Score: 46.04 E-value: 3.57e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617  261 GKRMELFCIYGGTPLPQTVWSKDGQRIQWSDR--ITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQSF 329
Cdd:cd05748     7 GESLRLDIPIKGRPTPTVTWSKDGQPLKETGRvqIETTASSTSLVIKNAKRSDSGKYTLTLKNSAGEKSAT 77

Immunoglobulin (Ig)-like domain found in Perlecan and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain found in Perlecan. Perlecan is a large multi-domain heparin sulfate proteoglycan, important in tissue development and organogenesis. Perlecan can be represented as 5 major portions; its fourth major portion (domain IV) is a tandem repeat of immunoglobulin-like domains (Ig2-Ig15) which can vary in size due to alternative splicing. Perlecan binds many cellular and extracellular ligands. Its domain IV region has many binding sites. Some of these have been mapped at the level of individual Ig-like domains, including a site restricted to the Ig5 domain for heparin/sulfatide, a site restricted to the Ig3 domain for nidogen-1 and nidogen-2, a site restricted to Ig4-5 for fibronectin, and sites restricted to Ig2 and to Ig13-15 for fibulin-2. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409412 Cd Length: 85 Bit Score: 46.01 E-value: 3.86e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  436 EAPAAVSTVDGRNVTIKCR-VNGSPKPLVKWLRasnwlTGGRYNVQA---NGDLEIQDVTFSDAGKYTCYAQNKFGEIQA 511
Cdd:cd05754     6 EEPRSQEVRPGADVSFICRaKSKSPAYTLVWTR-----VNGTLPSRAmdfNGILTIRNVQLSDAGTYVCTGSNMLDTDEA 80


                  ....
gi 281360617  512 DGSL 515
Cdd:cd05754    81 TATL 84

Second immunoglobulin (Ig)-like domain of protein tyrosine kinase (PTK) 7; The members here are composed of the second immunoglobulin (Ig)-like domain in protein tyrosine kinase (PTK) 7, also known as CCK4. PTK7 is a subfamily of the receptor protein tyrosine kinase family, and is referred to as an RPTK-like molecule. RPTKs transduce extracellular signals across the cell membrane and play important roles in regulating cell proliferation, migration, and differentiation. PTK7 is organized as an extracellular portion having seven Ig-like domains, a single transmembrane region, and a cytoplasmic tyrosine kinase-like domain. PTK7 is considered a pseudokinase as it has several unusual residues in some of the highly conserved tyrosine kinase (TK) motifs; it is predicted to lack TK activity. PTK7 may function as a cell-adhesion molecule. PTK7 mRNA is expressed at high levels in placenta, melanocytes, liver, lung, pancreas, and kidney. PTK7 is overexpressed in several cancers, including melanoma and colon cancer lines.

Pssm-ID: 409417 Cd Length: 95 Bit Score: 46.07 E-value: 4.71e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRN-VTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQANG---DLEIQDVTFSDAGKYTCYAQNKFG 507
Cdd:cd05760     1 PVVLKHPASAAEIQPSSrVTLRCHIDGHPRPTYQWFRDGTPLSDGQGNYSVSSkerTLTLRSAGPDDSGLYYCCAHNAFG 80


                  ..
gi 281360617  508 EI 509
Cdd:cd05760    81 SV 82

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 45.95 E-value: 4.93e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  259 LRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDRIT--QGHYGK-SLVIRQTNFDDAGTYTCDVSNGVGNAqSFSIILNV 335
Cdd:cd05744    13 QEGRLCRFDCKVSGLPTPDLFWQLNGKPVRPDSAHKmlVRENGRhSLIIEPVTKRDAGIYTCIARNRAGEN-SFNAELVV 91

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 45.95 E-value: 5.08e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  817 DAPTNFTMRQITSsTSGYMAWTPVSEESvrGHFKGYKIQtWTENEGEEGLREIHVKGDTHNALVTQFKPDSKNYARILAY 896
Cdd:cd00063     2 SPPTNLRVTDVTS-TSVTLSWTPPEDDG--GPITGYVVE-YREKGSGDWKEVEVTPGSETSYTLTGLKPGTEYEFRVRAV 77

                          90
                  ....*....|....*.
gi 281360617  897 NGRFNGPPSAVIDFDT 912
Cdd:cd00063    78 NGGGESPPSESVTVTT 93

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 45.69 E-value: 5.77e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  341 FTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKpIEQSTPNPRR---TVTDNTIRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd05763     2 FTKTPHDITIRAGSTARLECAATGHPTPQIAWQKDGG-TDFPAARERRmhvMPEDDVFFIVDVKIEDTGVYSCTAQNSAG 80

                          90
                  ....*....|
gi 281360617  418 YVYKDVYLNV 427
Cdd:cd05763    81 SISANATLTV 90

First Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409566 [Multi-domain] Cd Length: 93 Bit Score: 45.81 E-value: 5.87e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  523 ITQEPQNYEVAAGQSATFrcnEAHDDTLEI-EIDWWKDGQSIDFEAQPRF-VKTNDNS--LTIAKTMELDSGEYTCVART 598
Cdd:cd20974     3 FTQPLQSVVVLEGSTATF---EAHVSGKPVpEVSWFRDGQVISTSTLPGVqISFSDGRakLSIPAVTKANSGRYSLTATN 79

                          90
                  ....*....|...
gi 281360617  599 RLDEATARANLIV 611
Cdd:cd20974    80 GSGQATSTAELLV 92

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 45.48 E-value: 5.89e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  446 GRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQA-NGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSLVVK 518
Cdd:cd05731    10 GGVLLLECIAEGLPTPDIRWIKLGGELPKGRTKFENfNKTLKIENVSEADSGEYQCTASNTMGSARHTISVTVE 83

C-terminal immunoglobulin (Ig)-like domain of myotilin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myotilin. Mytolin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to the latter family contain multiple Ig-like domains and function as scaffolds, modulating the actin cytoskeleton. Myotilin is most abundant in skeletal and cardiac muscle and is involved in maintaining sarcomere integrity. It binds to alpha-actinin, filamin, and actin. Mutations in myotilin lead to muscle disorders. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409473 Cd Length: 92 Bit Score: 45.92 E-value: 5.93e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQANGD------LEIQDVTFSDAGKYTCYAQNK 505
Cdd:cd05892     1 PMFIQKPQNKKVLEGDPVRLECQISAIPPPQIFWKKNNEMLQYNTDRISLYQDncgricLLIQNANKKDAGWYTVSAVNE 80


                  ..
gi 281360617  506 FG 507
Cdd:cd05892    81 AG 82

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 45.69 E-value: 7.14e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  522 RITQEPQNYEVAAGQSATFRCNEahDDTLEIEIDWWKDGQSIDFEAQPRFVKTNDNSLTIAKTMELDSGEYTCVARTRLD 601
Cdd:cd05730     5 RARQSEVNATANLGQSVTLACDA--DGFPEPTMTWTKDGEPIESGEEKYSFNEDGSEMTILDVDKLDEAEYTCIAENKAG 82

                          90
                  ....*....|
gi 281360617  602 EATARANLIV 611
Cdd:cd05730    83 EQEAEIHLKV 92

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 45.77 E-value: 7.26e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWihngKPIEQSTP--------NPRRTVTDN-TIRIINLVKGDTGNYG 409
Cdd:cd20954     2 PRWIVEPVDANVAAGQDVMLHCQADGFPTPTVTW----KKATGSTPgeykdllyDPNVRILPNgTLVFGHVQKENEGHYL 77

                          90
                  ....*....|....*....
gi 281360617  410 CNATNSLGY-VYKDVYLNV 427
Cdd:cd20954    78 CEAKNGIGSgLSKVIFLKV 96

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 45.72 E-value: 7.42e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  341 FTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGK-----PIEQSTPNPRRTVTDN-TIRIINLVKGDTGNYGCNATN 414
Cdd:cd05726     2 FVVKPRDQVVALGRTVTFQCETKGNPQPAIFWQKEGSqnllfPYQPPQPSSRFSVSPTgDLTITNVQRSDVGYYICQALN 81

                          90
                  ....*....|...
gi 281360617  415 SLGYVYKDVYLNV 427
Cdd:cd05726    82 VAGSILAKAQLEV 94

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 45.26 E-value: 7.77e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617  358 FECRAAGVPEPKISWIHNGKPIEQStpnpRRTVTD-----NTIRIINLVKG-DTGNYGCNATNSLG 417
Cdd:cd20973    17 FDCKVEGYPDPEVKWMKDDNPIVES----RRFQIDqdedgLCSLIISDVCGdDSGKYTCKAVNSLG 78

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409442 Cd Length: 92 Bit Score: 45.62 E-value: 7.84e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  446 GRNVTIKCRVNGSPKPLVKWLRASNWLTG---GRyNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQA 511
Cdd:cd05856    19 GSSVRLKCVASGNPRPDITWLKDNKPLTPpeiGE-NKKKKWTLSLKNLKPEDSGKYTCHVSNRAGEINA 86

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 45.18 E-value: 7.84e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617  266 LFCIYGGTPLPQTVWSKDGQRIQWSD-RITQGHYGkSLVIRQTNFDDAGTYTCDVSNGVGNAqSFSIILNV 335
Cdd:cd20952    19 LNCQATGEPVPTISWLKDGVPLLGKDeRITTLENG-SLQIKGAEKSDTGEYTCVALNLSGEA-TWSAVLDV 87

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 45.58 E-value: 8.48e-06

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617   57 IECEADGQPEPEYSWIKNGKKFdwQAYDNR-MLRQPGRgTLVITIPKDEDRGHYQCFASNEFGTATS 122
Cdd:cd20970    22 FMCRAEGSPEPEISWTRNGNLI--IEFNTRyIVRENGT-TLTIRNIRRSDMGIYLCIASNGVPGSVE 85

First C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409474 Cd Length: 92 Bit Score: 45.47 E-value: 9.73e-06

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  445 DGRNVTIKCRVNGSPKPLVKWLRASNWLT--GGRYNVQANGD----LEIQDVTFSDAGKYTCYAQNKFGEIQADGSLVV 517
Cdd:cd05893    14 EGMPVTFTCRVAGNPKPKIYWFKDGKQISpkSDHYTIQRDLDgtcsLHTTASTLDDDGNYTIMAANPQGRISCTGRLMV 92

First immunoglobulin-like domains A168 within the A-band segment of human cardiac titin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domain A168 within the A-band segment of human cardiac titin. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structures of the titin-A168169 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409563 Cd Length: 93 Bit Score: 45.15 E-value: 9.82e-06

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  434 ISEAPAAVstvdGRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQANGD-----LEIQDVT-FSDAGKYTCYAQNKFG 507
Cdd:cd20971     8 LRNLNVRY----QSNATLVCKVTGHPKPIVKWYRQGKEIIADGLKYRIQEFkggyhQLIIASVtDDDATVYQVRATNQGG 83

Second C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409582 Cd Length: 91 Bit Score: 45.09 E-value: 1.02e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWL---TGGRYNVQANG--DLEIQDVTFSDAGKYTCYAQNKF 506
Cdd:cd20990     1 PHFLQAPGDLTVQEGKLCRMDCKVSGLPTPDLSWQLDGKPIrpdSAHKMLVRENGvhSLIIEPVTSRDAGIYTCIATNRA 80

                          90
                  ....*....|.
gi 281360617  507 GEIQADGSLVV 517
Cdd:cd20990    81 GQNSFNLELVV 91

Third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein) and similar proteins. WFIKKN is a secreted protein that consists of multiple types of protease inhibitory modules, including two tandem Kunitz-type protease inhibitor-domains. The Ig superfamily is a heterogenous group of proteins built on a common fold comprised of a sandwich of two beta sheets. Members of the Ig superfamily are components of immunoglobulin, neuroglia, cell surface glycoproteins, such as T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, such as butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409422 [Multi-domain] Cd Length: 95 Bit Score: 45.23 E-value: 1.04e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNwltgGRYN-------VQAN------GDLEIQDVTFSDAGKY 498
Cdd:cd05765     1 PALVNSPTHQTVKVGETASFHCDVTGRPQPEITWEKQVP----GKENlimrpnhVRGNvvvtniGQLVIYNAQPQDAGLY 76

                          90
                  ....*....|....*....
gi 281360617  499 TCYAQNKFGEIQADGSLVV 517
Cdd:cd05765    77 TCTARNSGGLLRANFPLSV 95

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 45.29 E-value: 1.10e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617  261 GKRMELFCIYGGTPLPQTVWSKDGQRIQWSDRITQGHYGK---SLVIRQTNFDDAGTYTCDVSNGVG 324
Cdd:cd05729    19 ANKVRLECGAGGNPMPNITWLKDGKEFKKEHRIGGTKVEEkgwSLIIERAIPRDKGKYTCIVENEYG 85

Sixth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the sixth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409551 Cd Length: 94 Bit Score: 44.79 E-value: 1.43e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  245 PPVRQYVSRRQSLALRGKRMELFCIYGGTPLPQTV-WSKDGQRIQWSDRITQ---GHYGKSLVIRQTNFDDAGTYTCDVS 320
Cdd:cd20959     1 PPRIIPFAFGEGAAQVGMRAQLHCGVPGGDLPLNIrWTLDGQPISDDLGITVsrlGRRSSILSIDSLEASHAGNYTCHAR 80

                          90
                  ....*....|....*
gi 281360617  321 NGVGNAQsFSIILNV 335
Cdd:cd20959    81 NSAGSAS-YTAPLTV 94

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 44.76 E-value: 1.46e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  131 ELNAFKdeaaKTLEAVEGEPFMLKCAaPDGFPSPTVNWMiqesiDGSIKSINNSRMTLDPEGNLWFSNVTREDASSdfyY 210
Cdd:cd04969     4 ELNPVK----KKILAAKGGDVIIECK-PKASPKPTISWS-----KGTELLTNSSRICILPDGSLKIKNVTKSDEGK---Y 70


                  ....*...
gi 281360617  211 ACSATSVF 218
Cdd:cd04969    71 TCFAVNFF 78

Immunoglobulin (Ig)-like domain of titin and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain found in titin-like proteins and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is a giant protein; depending on isoform composition, it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone. It appears to function similarly to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. Within the sarcomere, titin is also attached to or is associated with myosin binding protein C (MyBP-C). MyBP-C appears to contribute to the generation of passive tension by titin and like titin has repeated Ig-like and FN-III domains. Also included in this group are worm twitchin and insect projectin, thick filament proteins of invertebrate muscle which also have repeated Ig-like and FN-III domains.

Pssm-ID: 409406 [Multi-domain] Cd Length: 82 Bit Score: 44.50 E-value: 1.52e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617  446 GRNVTIKCRVNGSPKPLVKWLRA-SNWLTGGRYNVQANGD---LEIQDVTFSDAGKYTCYAQNKFGEIQADGSLVV 517
Cdd:cd05748     7 GESLRLDIPIKGRPTPTVTWSKDgQPLKETGRVQIETTASstsLVIKNAKRSDSGKYTLTLKNSAGEKSATINVKV 82

Immunoglobulin (Ig)-like domain of human titin C terminus and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain from the C-terminus of human titin x and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is gigantic; depending on isoform composition it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone and appears to function similar to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 143224 [Multi-domain] Cd Length: 92 Bit Score: 44.65 E-value: 1.56e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617  344 EPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNP-RRTVTDNTIRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd05747     9 KPRSLTVSEGESARFSCDVDGEPAPTVTWMREGQIIVSSQRHQiTSTEYKSTFEISKVQMSDEGNYTVVVENSEG 83

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 44.60 E-value: 1.64e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  350 AAEDEEVVFECRAAGVPEPKISWihnGKPIEQSTPNPRRTV-TDNTIRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd05852    14 AAKGGRVIIECKPKAAPKPKFSW---SKGTELLVNNSRISIwDDGSLEILNITKLDEGSYTCFAENNRG 79

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three IG-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans.

Pssm-ID: 409443 [Multi-domain] Cd Length: 95 Bit Score: 44.46 E-value: 1.71e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  356 VVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTDNTIRII--NLVKGDTGNYGCNATNSLGYVYKDVYLNV 427
Cdd:cd05857    22 VKFRCPAAGNPTPTMRWLKNGKEFKQEHRIGGYKVRNQHWSLImeSVVPSDKGNYTCVVENEYGSINHTYHLDV 95

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 44.55 E-value: 1.73e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617  139 AAKTLEAVEGEPFMLKCAApDGFPSPTVNWMiqesIDGSIKSINNSRMTLDPE-GNLWFSNVTREDASSdfyYACSA 214
Cdd:cd20976     7 VPKDLEAVEGQDFVAQCSA-RGKPVPRITWI----RNAQPLQYAADRSTCEAGvGELHIQDVLPEDHGT---YTCLA 75

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 44.46 E-value: 1.97e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  522 RITQEPQNYEVAAGQSATFRCNEAHDDTLEIEidWWKDGQSID---FEAQPRFVKTNDNSLTIAKTM-----ELDSGEYT 593
Cdd:cd07693     2 RIVEHPSDLIVSKGDPATLNCKAEGRPTPTIQ--WLKNGQPLEtdkDDPRSHRIVLPSGSLFFLRVVhgrkgRSDEGVYV 79

                          90
                  ....*....|...
gi 281360617  594 CVARTRLDEATAR 606
Cdd:cd07693    80 CVAHNSLGEAVSR 92

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 44.56 E-value: 2.04e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617   45 AQQNKESDNpfiIECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRqpGRGT-LVITIPKDEDRGHYQCFASNEFG 118
Cdd:cd05736    11 AKEPGVEAS---LRCHAEGIPLPRVQWLKNGMDINPKLSKQLTLI--ANGSeLHISNVRYEDTGAYTCIAKNEGG 80

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 43.71 E-value: 2.10e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617   141 KTLEAVEGEPFMLKCAApDGFPSPTVNWMIQESIDGSIKSInnSRMTLDPEGNLWFSNVTREDASsdfYYACSAT 215
Cdd:pfam13927    9 SSVTVREGETVTLTCEA-TGSPPPTITWYKNGEPISSGSTR--SRSLSGSNSTLTISNVTRSDAG---TYTCVAS 77

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 44.06 E-value: 2.23e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  345 PEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTpnPRRTVTDNTIRIINLVKGDTGNYGCNATN 414
Cdd:cd20957     8 PPVQTVDFGRTAVFNCSVTGNPIHTVLWMKDGKPLGHSS--RVQILSEDVLVIPSVKREDKGMYQCFVRN 75

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 44.06 E-value: 2.42e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617   59 CEADGQPEPEYSWIKNGKKFdwqAYDNRmLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATS 122
Cdd:cd20957    23 CSVTGNPIHTVLWMKDGKPL---GHSSR-VQILSEDVLVIPSVKREDKGMYQCFVRNDGDSAQA 82

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 44.04 E-value: 2.45e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  446 GRNVTIKCR-VNGSPKPLVKWLRASNWLTGGR------YNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSLVV 517
Cdd:cd05750    14 GSKLVLKCEaTSENPSPRYRWFKDGKELNRKRpknikiRNKKKNSELQINKAKLEDSGEYTCVVENILGKDTVTGNVTV 92

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 409395 [Multi-domain] Cd Length: 96 Bit Score: 44.05 E-value: 2.60e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  349 TAAEDEEVVFECRAAGVPEPKISWIHNGKPI--EQSTPNPRRTVTDN------TIRIINLVkgDTGNYGCNATNSLGYVY 420
Cdd:cd05732    12 TAVELEQITLTCEAEGDPIPEITWRRATRGIsfEEGDLDGRIVVRGHarvsslTLKDVQLT--DAGRYDCEASNRIGGDQ 89


                  ....*..
gi 281360617  421 KDVYLNV 427
Cdd:cd05732    90 QSMYLEV 96

C-terminal immunoglobulin (Ig)-like domain of myotilin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myotilin. Mytolin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to the latter family contain multiple Ig-like domains and function as scaffolds, modulating the actin cytoskeleton. Myotilin is most abundant in skeletal and cardiac muscle and is involved in maintaining sarcomere integrity. It binds to alpha-actinin, filamin, and actin. Mutations in myotilin lead to muscle disorders. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409473 Cd Length: 92 Bit Score: 43.99 E-value: 2.64e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTpNPRRTVTDNTIRIINLVKG----DTGNYGCNATN 414
Cdd:cd05892     1 PMFIQKPQNKKVLEGDPVRLECQISAIPPPQIFWKKNNEMLQYNT-DRISLYQDNCGRICLLIQNankkDAGWYTVSAVN 79

                          90
                  ....*....|...
gi 281360617  415 SLGYVYKDVYLNV 427
Cdd:cd05892    80 EAGVVSCNARLDV 92

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 43.76 E-value: 2.75e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  433 TISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRasnwlTGG---------RYNVQANGD-LEIQDVTFSDAGKYTCYA 502
Cdd:cd05763     1 SFTKTPHDITIRAGSTARLECAATGHPTPQIAWQK-----DGGtdfpaarerRMHVMPEDDvFFIVDVKIEDTGVYSCTA 75

                          90
                  ....*....|....*
gi 281360617  503 QNKFGEIQADGSLVV 517
Cdd:cd05763    76 QNSAGSISANATLTV 90

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409442 Cd Length: 92 Bit Score: 44.08 E-value: 2.76e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617  253 RRQSLALR-GKRMELFCIYGGTPLPQTVWSKDGQRIqwsDRITQGHYGK---SLVIRQTNFDDAGTYTCDVSNGVG 324
Cdd:cd05856    10 RRRVIARPvGSSVRLKCVASGNPRPDITWLKDNKPL---TPPEIGENKKkkwTLSLKNLKPEDSGKYTCHVSNRAG 82

C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein (also known as myomesin-2). Myomesin and M-protein are both structural proteins localized to the M-band, a transverse structure in the center of the sarcomere, and are candidates for M-band bridges. Both proteins are modular, consisting mainly of repetitive Ig-like and fibronectin type III (FnIII) domains. Myomesin is expressed in all types of vertebrate striated muscle; M-protein has a muscle-type specific expression pattern. Myomesin is present in both slow and fast fibers; M-protein is present only in fast fibers. It has been suggested that myomesin acts as a molecular spring with alternative splicing as a means of modifying its elasticity.

Pssm-ID: 319300 Cd Length: 92 Bit Score: 43.73 E-value: 2.99e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  345 PEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTP-----NPRRTVtdnTIRIINLVKGDTGNYGCNATNSLGYV 419
Cdd:cd05737     8 PDVVTIMEGKTLNLTCNVWGDPPPEVSWLKNDQALAFLDHcnlkvEAGRTV---YFTINGVSSEDSGKYGLVVKNKYGSE 84


                  ....*...
gi 281360617  420 YKDVYLNV 427
Cdd:cd05737    85 TSDVTVSV 92

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 43.79 E-value: 3.10e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  245 PPVRQYvSRRQSLALrGKRMELFCIYGGTPLPQTVWSKDGQRI--QWSDRITQGHYGKSLVIRQTNFDDAGTYTCDVSNG 322
Cdd:cd05736     1 PVIRVY-PEFQAKEP-GVEASLRCHAEGIPLPRVQWLKNGMDInpKLSKQLTLIANGSELHISNVRYEDTGAYTCIAKNE 78


                  ..
gi 281360617  323 VG 324
Cdd:cd05736    79 GG 80

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 43.54 E-value: 3.14e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  438 PAAVSTVDGRNVTIKCRV-NGSPKPLVKWLRASNWL--TGGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGE-IQADG 513
Cdd:cd05724     4 PSDTQVAVGEMAVLECSPpRGHPEPTVSWRKDGQPLnlDNERVRIVDDGNLLIAEARKSDEGTYKCVATNMVGErESRAA 83


                  ....
gi 281360617  514 SLVV 517
Cdd:cd05724    84 RLSV 87

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 43.36 E-value: 3.24e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617  252 SRRQSLALRGKRMELFCIYGGTPLPQTVWSKDGQRIQwSDRITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQ 327
Cdd:cd05876     1 SSSSLVALRGQSLVLECIAEGLPTPTVKWLRPSGPLP-PDRVKYQNHNKTLQLLNVGESDDGEYVCLAENSLGSAR 75

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 43.79 E-value: 3.26e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  526 EPQNYEVAAGQSATFRCnEAHDDTlEIEIDWWKDG-QSIDFEAQP-----RFVKTNDNSLTIAKTMELDSGEYTCVARTR 599
Cdd:cd05726     5 KPRDQVVALGRTVTFQC-ETKGNP-QPAIFWQKEGsQNLLFPYQPpqpssRFSVSPTGDLTITNVQRSDVGYYICQALNV 82

                          90
                  ....*....|....*
gi 281360617  600 LDEATARANLIVQDV 614
Cdd:cd05726    83 AGSILAKAQLEVTDV 97

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 43.56 E-value: 3.57e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  523 ITQEPQNYEVAAGQSATFRCNEAHDDTLEIEidWWKDGQSIDFEAQPR----FVKTNDNSLTIAKTMELDSGEYTCVART 598
Cdd:cd20951     3 FIIRLQSHTVWEKSDAKLRVEVQGKPDPEVK--WYKNGVPIDPSSIPGkykiESEYGVHVLHIRRVTVEDSAVYSAVAKN 80

                          90
                  ....*....|....
gi 281360617  599 RLDEATARANLIVQ 612
Cdd:cd20951    81 IHGEASSSASVVVE 94

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 43.30 E-value: 3.71e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  343 KEPEIATAAEDEEVVFECRAAGVPEPKISWihnGKPIEQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLGyvyKD 422
Cdd:cd04968     6 RFPADTYALKGQTVTLECFALGNPVPQIKW---RKVDGSPSSQWEITTSEPVLEIPNVQFEDEGTYECEAENSRG---KD 79


                  ..
gi 281360617  423 VY 424
Cdd:cd04968    80 TV 81

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 43.29 E-value: 3.86e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  527 PQNYEVAAGQSATFRC----NEAHddtleiEIDWWKDGQSIdfEAQPRFVKTNDNSLTIAKTMELDSGEYTCVARTRLDE 602
Cdd:cd20957     8 PPVQTVDFGRTAVFNCsvtgNPIH------TVLWMKDGKPL--GHSSRVQILSEDVLVIPSVKREDKGMYQCFVRNDGDS 79


                  ....*..
gi 281360617  603 ATARANL 609
Cdd:cd20957    80 AQATAEL 86

Fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule); The members here are composed of the fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six IG-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409454 Cd Length: 89 Bit Score: 43.43 E-value: 3.88e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617   59 CEADGQPEPEYSWIKNGKKFDWQAYDNRmlRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNS 124
Cdd:cd05868    21 CRANGNPKPSISWLTNGVPIEIAPTDPS--RKVDGDTIIFSKVQERSSAVYQCNASNEYGYLLANA 84

Fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409453 [Multi-domain] Cd Length: 89 Bit Score: 43.35 E-value: 3.88e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281360617   57 IECEADGQPEPEYSWIKNGKKFDWQAYDNRmlRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNS-VYV 127
Cdd:cd05867    19 LDCQVEGIPTPNITWSINGAPIEGTDPDPR--RHVSSGALILTDVQPSDTAVYQCEARNRHGNLLANAhVHV 88

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 43.75 E-value: 3.92e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281360617  446 GRNVTIKCRVNGSPKPLVKWLRAS------NWLTGGRyNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQA 511
Cdd:cd05729    19 ANKVRLECGAGGNPMPNITWLKDGkefkkeHRIGGTK-VEEKGWSLIIERAIPRDKGKYTCIVENEYGSINH 89

Sixth immunoglobulin (Ig) domain of contactin; The members here are composed of the sixth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409359 Cd Length: 102 Bit Score: 43.69 E-value: 4.03e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  430 EPPTISEAPAAVSTVDGRNVTIKCRV--------------NGSPKPLVKwlraSNWLTGGRYNVQANGDLEIQDVTFSDA 495
Cdd:cd04970     1 DATRITLAPSNADITVGENATLQCHAshdptldltftwsfNGVPIDLEK----IEGHYRRRYGKDSNGDLEIVNAQLKHA 76

                          90       100
                  ....*....|....*....|...
gi 281360617  496 GKYTCYAQNKFGEIQADGSLVVK 518
Cdd:cd04970    77 GRYTCTAQTVVDSDSASATLVVR 99

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 43.69 E-value: 4.30e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWL------TGGRYNVQANGDLEIQDVTF-----SDAGKYTC 500
Cdd:cd07693     1 PRIVEHPSDLIVSKGDPATLNCKAEGRPTPTIQWLKNGQPLetdkddPRSHRIVLPSGSLFFLRVVHgrkgrSDEGVYVC 80

                          90
                  ....*....|....*...
gi 281360617  501 YAQNKFGE-IQADGSLVV 517
Cdd:cd07693    81 VAHNSLGEaVSRNASLEV 98

IL-beta-binding protein; Provisional

Pssm-ID: 165149 [Multi-domain] Cd Length: 326 Bit Score: 46.93 E-value: 4.34e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  327 QSFSIILNVNSVPYFTKEPEIataaEDEEVVFECraagvpePKISWIHNGKPI------EQSTPNPRRTVTDN--TIRII 398
Cdd:PHA02785   19 QTFNAPECIDKGQYFASFMEL----ENEPVILPC-------PQINTLSSGYNIldilweKRGADNDRIIPIDNgsNMLIL 87

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  399 NLVKGDTGNYGCNATN-------SLGYVYKDVY---LNVQAEPPTISEAPAAVSTVDGRNVTIKCRVNGSpkplVKWlRA 468
Cdd:PHA02785   88 NPTQSDSGIYICITKNetycdmmSLNLTIVSVSesnIDLISYPQIVNERSTGEMVCPNINAFIASNVNAD----IIW-SG 162

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  469 SNWLTGGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSLVVKEHTR------ITQEPQNYEVAAGQSATFRC 542
Cdd:PHA02785  163 HRRLRNKRLKQRTPGIITIEDVRKNDAGYYTCVLKYIYGDKTYNVTRIVKLEVRdriippTMQLPEGVVTSIGSNLTIAC 242

                         250       260       270       280       290       300       310
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617  543 NEA-HDDTLEIEIDWWKDG---QSIDFEAQPRFVKTND-----------NSLTIAKTMELDSGEYTCVART 598
Cdd:PHA02785  243 RVSlRPPTTDADVFWISNGmyyEEDDEDGDGRISVANKiyttdkrrvitSRLNINPVKEEDATTFTCMAFT 313

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 43.56 E-value: 4.38e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  249 QYVSRRQSLAL-RGKRMELFCIYGGTPLPQTVWSKDGQRIQWS----DRITQGHYGKS-LVIRQTNFDDAGTYTCDVSNG 322
Cdd:cd20951     2 EFIIRLQSHTVwEKSDAKLRVEVQGKPDPEVKWYKNGVPIDPSsipgKYKIESEYGVHvLHIRRVTVEDSAVYSAVAKNI 81


                  ....*.
gi 281360617  323 VGNAQS 328
Cdd:cd20951    82 HGEASS 87

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 43.15 E-value: 4.41e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281360617    54 PFIIECEADGQPEPEYSWIKNGKkfdwqaydnrmlRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNSV 125
Cdd:pfam13895   16 PVTLTCSAPGNPPPSYTWYKDGS------------AISSSPNFFTLSVSAEDSGTYTCVARNGRGGKVSNPV 75

First immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409436 [Multi-domain] Cd Length: 95 Bit Score: 43.40 E-value: 5.05e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   49 KESDNPFIIECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRqpgrGTLVITIP-KDEDRGHYQCFASNEFGTatsnsVYV 127
Cdd:cd05849    16 ESTEGKVSVNCRARANPFPIYKWRKNNLDIDLTNDRYSMVG----GNLVINNPdKYKDAGRYVCIVSNIYGK-----VRS 86


                  ....*.
gi 281360617  128 RKAELN 133
Cdd:cd05849    87 REATLS 92

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 42.95 E-value: 5.25e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281360617   349 TAAEDEEVVFECRA-AGVPEPKISWIHNGKPIEQSTPNP--RRTVTDNTIRIINLVKGDTGNYGCNATNSLG 417
Cdd:pfam00047    7 TVLEGDSATLTCSAsTGSPGPDVTWSKEGGTLIESLKVKhdNGRTTQSSLLISNVTKEDAGTYTCVVNNPGG 78

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 42.96 E-value: 5.43e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  522 RITQEPQNYEVAAGQSATFRCNEAHDDTLEIEidWWKDGQSIdfEAQPRFVKTND---NSLTIAKTMELDSGEYTCVART 598
Cdd:cd20972     3 QFIQKLRSQEVAEGSKVRLECRVTGNPTPVVR--WFCEGKEL--QNSPDIQIHQEgdlHSLIIAEAFEEDTGRYSCLATN 78

                          90
                  ....*....|...
gi 281360617  599 RLDEATARANLIV 611
Cdd:cd20972    79 SVGSDTTSAEIFV 91

Second immunoglobulin (Ig)-like domain of Kirrel (kin of irregular chiasm-like) 3, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain of Kirrel (kin of irregular chiasm-like) 3 (also known as Neph2). This protein has five Ig-like domains, one transmembrane domain, and a cytoplasmic tail. Included in this group is mammalian Kirrel (Neph1), Kirrel2 (Neph3), and Drosophila RST (irregular chiasm C-roughest) protein. These proteins contain multiple Ig domains, have properties of cell adhesion molecules, and are important in organ development.

Pssm-ID: 409416 Cd Length: 98 Bit Score: 43.21 E-value: 5.53e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   52 DNPFIIECEADG-QPEPEYSWIKNGKKFDWQAYDNRMLRQPGRGTLVITI---PKDEDRGH-YQCFASNE 116
Cdd:cd05759    15 GVPYNLTCRARGaKPAAEIIWFRDGEQLEGAVYSKELLKDGKRETTVSTLlitPSDLDTGRtFTCRARNE 84

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 42.17 E-value: 6.49e-05

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617   57 IECEADGQPEPEYSWIKNGKkfdwQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNSV 125
Cdd:cd05746     3 IPCSAQGDPEPTITWNKDGV----QVTESGKFHISPEGYLAIRDVGVADQGRYECVARNTIGYASVSMV 67

Immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409397 [Multi-domain] Cd Length: 97 Bit Score: 42.86 E-value: 6.82e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  431 PPTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASN---------WLTGGRYNVQANGDLEIQDVTFSDAGKYTCY 501
Cdd:cd05734     1 PPRFVVQPNDQDGIYGKAVVLNCSADGYPPPTIVWKHSKGsgvpqfqhiVPLNGRIQLLSNGSLLIKHVLEEDSGYYLCK 80


                  ....*.
gi 281360617  502 AQNKFG 507
Cdd:cd05734    81 VSNDVG 86

Immunoglobulin (Ig)-like domain of human carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) domains 2, 4, and 6, and similar domains; The members here are composed of the second, fourth, and sixth immunoglobulin (Ig)-like domains in human carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) protein subfamily. The CEA family is a group of anchored or secreted glycoproteins expressed by epithelial cells, leukocytes, endothelial cells, and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. This group represents the CEACAM subfamily. CEACAM1 has many important cellular functions; it is a cell adhesion molecule and a signaling molecule that regulates the growth of tumor cells, an angiogenic factor, and a receptor for bacterial and viral pathogens, including mouse hepatitis virus (MHV). In mice, four isoforms of CEACAM1 generated by alternative splicing have either two [D1, D4] or four [D1-D4] Ig-like domains on the cell surface.

Pssm-ID: 409402 [Multi-domain] Cd Length: 89 Bit Score: 42.77 E-value: 7.17e-05

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617  280 WSKDGQRIQWSDRITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQSFSIILNVN 336
Cdd:cd05740    33 WWFNGQSLPVTPRLTLSNGNRTLTLLNVTREDAGAYQCEISNPVSANRSDPVTLDVI 89

Immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409397 [Multi-domain] Cd Length: 97 Bit Score: 42.86 E-value: 7.30e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHN---GKPIEQSTP--NPR-RTVTDNTIRIINLVKGDTGNYGCNA 412
Cdd:cd05734     2 PRFVVQPNDQDGIYGKAVVLNCSADGYPPPTIVWKHSkgsGVPQFQHIVplNGRiQLLSNGSLLIKHVLEEDSGYYLCKV 81

                          90
                  ....*....|....*.
gi 281360617  413 TNSLGY-VYKDVYLNV 427
Cdd:cd05734    82 SNDVGAdISKSMYLTV 97

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 42.50 E-value: 8.84e-05

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281360617  525 QEPQNYEVAAGQSATFRCneAHDDTLEIEIDWWKDGQSIDFEAQPRFVKTNDNSLTIAKTMELDSGEYTCVA 596
Cdd:cd20970     7 QPSFTVTAREGENATFMC--RAEGSPEPEISWTRNGNLIIEFNTRYIVRENGTTLTIRNIRRSDMGIYLCIA 76

Second C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409582 Cd Length: 91 Bit Score: 42.39 E-value: 9.58e-05

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   36 APGELlfkVAQQNKESDnpfiIECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASN 115
Cdd:cd20990     6 APGDL---TVQEGKLCR----MDCKVSGLPTPDLSWQLDGKPIRPDSAHKMLVRENGVHSLIIEPVTSRDAGIYTCIATN 78


                  ...
gi 281360617  116 EFG 118
Cdd:cd20990    79 RAG 81

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 42.17 E-value: 1.06e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617   54 PFIIECEADGQPEPEYSWIKNGKkfdwQAYDNRmlRQ---PGrGTLVIT-IPKDEDRGHYQCFASNEFGTATSNSVYVR 128
Cdd:cd20958    17 TLRLHCPVAGYPISSITWEKDGR----RLPLNH--RQrvfPN-GTLVIEnVQRSSDEGEYTCTARNQQGQSASRSVFVK 88

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 42.13 E-value: 1.08e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617  261 GKRMELFCIYGGTPLPQTVWSKDGQRIQWSDRItQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQS 328
Cdd:cd20957    16 GRTAVFNCSVTGNPIHTVLWMKDGKPLGHSSRV-QILSEDVLVIPSVKREDKGMYQCFVRNDGDSAQA 82

Second immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains.

Pssm-ID: 409400 [Multi-domain] Cd Length: 91 Bit Score: 42.31 E-value: 1.12e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  433 TISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLR----ASNWLTGGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFG 507
Cdd:cd05738     1 IIDMGPQLKVVEKARTATMLCAASGNPDPEISWFKdflpVDTATSNGRIKQLRSGALQIENSEESDQGKYECVATNSAG 79

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 41.93 E-value: 1.41e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617  522 RITQEPQNYEVAAGQSATFRCNEAHDDtlEIEIDWWKDGQSIDFEAQ--PRFvKTNDNSLTIAKTMELDSGEYTCVAR 597
Cdd:cd20949     1 TFTENAYVTTVKEGQSATILCEVKGEP--QPNVTWHFNGQPISASVAdmSKY-RILADGLLINKVTQDDTGEYTCRAY 75

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 42.11 E-value: 1.44e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  343 KEPEIATAAEDEEVVFECRAAGV-PEPKISWIHNGKPIEQSTPNP---RRTVTDNTIRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd05750     4 KEMKSQTVQEGSKLVLKCEATSEnPSPRYRWFKDGKELNRKRPKNikiRNKKKNSELQINKAKLEDSGEYTCVVENILG 82

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 41.69 E-value: 1.58e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617   57 IECEADGQPEPEYSWIkngkkfdwqAYDNRMLRQPGR------GTLVITIPKDEDRGHYQCFASNEFGTAT 121
Cdd:cd05764    20 LRCKARGDPEPAIHWI---------SPEGKLISNSSRtlvydnGTLDILITTVKDTGAFTCIASNPAGEAT 81

Immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409397 [Multi-domain] Cd Length: 97 Bit Score: 41.71 E-value: 1.69e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   28 PPRITKQPApgellfkvaQQNKESDNPFIIECEADGQPEPEYSWiKNGK-----KFDWQAYDNRMLRQPGRGTLVITIPK 102
Cdd:cd05734     1 PPRFVVQPN---------DQDGIYGKAVVLNCSADGYPPPTIVW-KHSKgsgvpQFQHIVPLNGRIQLLSNGSLLIKHVL 70

                          90       100
                  ....*....|....*....|....
gi 281360617  103 DEDRGHYQCFASNEFGTATSNSVY 126
Cdd:cd05734    71 EEDSGYYLCKVSNDVGADISKSMY 94

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 41.45 E-value: 1.71e-04

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617    716 NPDNVVGQGTEPNNLVISWTPMPEIEHNAPNFHYYVSWKRDIPaaAWENNNiFDWRQNNIVIADQPTFVKYLIKVVAIND 795
Cdd:smart00060    3 PPSNLRVTDVTSTSVTLSWEPPPDDGITGYIVGYRVEYREEGS--EWKEVN-VTPSSTSYTLTGLKPGTEYEFRVRAVNG 79


                    ....
gi 281360617    796 RGES 799
Cdd:smart00060   80 AGEG 83

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 41.52 E-value: 1.87e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281360617   56 IIECEADGQPEPEYSWiknGKKFDWQAYDNRMLRQPGRGTLVITIPKDeDRGHYQCFASNEFGTATSNSVYV 127
Cdd:cd05852    21 IIECKPKAAPKPKFSW---SKGTELLVNNSRISIWDDGSLEILNITKL-DEGSYTCFAENNRGKANSTGVLS 88

Immunoglobulin (Ig)-like domain of human neurofascin (NF); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of human neurofascin (NF). NF belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and a cytoplasmic domain. NF has many alternatively spliced isoforms having different temporal expression patterns during development. NF participates in axon subcellular targeting and synapse formation, however little is known of the functions of the different isoforms. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409459 Cd Length: 95 Bit Score: 41.88 E-value: 1.89e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGR-NVTIKCRVNGSPKPLVKWLRASNWLTGG---RYNVQA-NGDLEIQdvtFSDA-------GKYT 499
Cdd:cd05875     1 PTITKQSAKDYIVDPRdNILIECEAKGNPVPTFHWTRNGKFFNVAkdpRVSMRRrSGTLVID---FRGGgrpedyeGEYQ 77


                  ....*...
gi 281360617  500 CYAQNKFG 507
Cdd:cd05875    78 CFARNKFG 85

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 41.41 E-value: 1.92e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617   57 IECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTAT 121
Cdd:cd20973    17 FDCKVEGYPDPEVKWMKDDNPIVESRRFQIDQDEDGLCSLIISDVCGDDSGKYTCKAVNSLGEAT 81

First immunoglobulin (Ig)-like domain of Fcgamma-receptors (FcgammaRs), and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain of Fcgamma-receptors (FcgammaRs). Interactions between IgG and FcgammaR are important to the initiation of cellular and humoral response. IgG binding to FcgammaR leads to a cascade of signals and ultimately to functions such as antibody-dependent-cellular-cytotoxicity (ADCC), endocytosis, phagocytosis, release of inflammatory mediators, etc. FcgammaR has two Ig-like domains. This group also contains FcepsilonRI which binds IgE with high affinity.

Pssm-ID: 409410 [Multi-domain] Cd Length: 79 Bit Score: 40.81 E-value: 2.32e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  344 EPEIATAAEDEEVVFECRAAGVPEP-KISWIHNGKPIEQSTpnprrtvtdNTIRIINLVKGDTGNYGCNATNSlgYVYKD 422
Cdd:cd05752     6 DPPWTTVFQGEKVTLTCQGFYSPEQnSTQWYHNGTLISSTS---------SSYRIVAATVNDSGEYRCQTQGS--SLSDP 74


                  ....*
gi 281360617  423 VYLNV 427
Cdd:cd05752    75 VHLEV 79

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409442 Cd Length: 92 Bit Score: 41.38 E-value: 2.44e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617  356 VVFECRAAGVPEPKISWIHNGKPIEQSTP-NPRRtvTDNTIRIINLVKGDTGNYGCNATNSLGYV 419
Cdd:cd05856    22 VRLKCVASGNPRPDITWLKDNKPLTPPEIgENKK--KKWTLSLKNLKPEDSGKYTCHVSNRAGEI 84

C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein (also known as myomesin-2). Myomesin and M-protein are both structural proteins localized to the M-band, a transverse structure in the center of the sarcomere, and are candidates for M-band bridges. Both proteins are modular, consisting mainly of repetitive Ig-like and fibronectin type III (FnIII) domains. Myomesin is expressed in all types of vertebrate striated muscle; M-protein has a muscle-type specific expression pattern. Myomesin is present in both slow and fast fibers; M-protein is present only in fast fibers. It has been suggested that myomesin acts as a molecular spring with alternative splicing as a means of modifying its elasticity.

Pssm-ID: 319300 Cd Length: 92 Bit Score: 41.04 E-value: 2.59e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  438 PAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLT-GGRYNVQANGDLE----IQDVTFSDAGKYTCYAQNKFGEIQAD 512
Cdd:cd05737     8 PDVVTIMEGKTLNLTCNVWGDPPPEVSWLKNDQALAfLDHCNLKVEAGRTvyftINGVSSEDSGKYGLVVKNKYGSETSD 87


                  ....*
gi 281360617  513 GSLVV 517
Cdd:cd05737    88 VTVSV 92

Third immunoglobulin (Ig)-like domain of fibroblast growth factor receptor (FGFR); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain of fibroblast growth factor receptor (FGFR). Fibroblast growth factors (FGFs) participate in morphogenesis, development, angiogenesis, and wound healing. These FGF-stimulated processes are mediated by four FGFR tyrosine kinases (FGRF1-4). FGFRs are comprised of an extracellular portion consisting of three Ig-like domains, a transmembrane helix, and a cytoplasmic portion having protein tyrosine kinase activity. The highly conserved Ig-like domains 2 and 3, and the linker region between D2 and D3 define a general binding site for FGFs. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409363 Cd Length: 102 Bit Score: 41.64 E-value: 2.62e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  438 PAAVSTVDGRNVTIKCRVNGSPKPLVKWLRaSNWLTGGRY--------------NVQANGDLE---IQDVTFSDAGKYTC 500
Cdd:cd04974     8 PANQTVVLGSDVEFHCKVYSDAQPHIQWLK-HVEVNGSKYgpdglpyvtvlkvaGVNTTGEENtltISNVTFDDAGEYIC 86


                  ....*..
gi 281360617  501 YAQNKFG 507
Cdd:cd04974    87 LAGNSIG 93

First immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409547 Cd Length: 99 Bit Score: 41.24 E-value: 2.63e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   57 IECEADGQPEPEYSWIKNgkkfDWQAY-DNRMLRQ-PGRGTLVITIPKDEDRGH------YQCFASNEFGTATSNSVYVR 128
Cdd:cd20955    22 IECKASGNPMPEIIWIRS----DGTAVgDVPGLRQiSSDGKLVFPPFRAEDYRQevhaqvYACLARNQFGSIISRDVHVR 97

C-terminal immunoglobulin (Ig)-like domain of myotilin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myotilin. Mytolin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to the latter family contain multiple Ig-like domains and function as scaffolds, modulating the actin cytoskeleton. Myotilin is most abundant in skeletal and cardiac muscle and is involved in maintaining sarcomere integrity. It binds to alpha-actinin, filamin, and actin. Mutations in myotilin lead to muscle disorders. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409473 Cd Length: 92 Bit Score: 41.29 E-value: 2.73e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617  258 ALRGKRMELFCIYGGTPLPQTVWSKDGQRIQWS-DRIT--QGHYGK-SLVIRQTNFDDAGTYTCDVSNGVG 324
Cdd:cd05892    12 VLEGDPVRLECQISAIPPPQIFWKKNNEMLQYNtDRISlyQDNCGRiCLLIQNANKKDAGWYTVSAVNEAG 82

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 41.03 E-value: 2.94e-04

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617    53 NPFIIECEA-DGQPEPEYSWIKNGKKFDWQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATS 122
Cdd:pfam00047   12 DSATLTCSAsTGSPGPDVTWSKEGGTLIESLKVKHDNGRTTQSSLLISNVTKEDAGTYTCVVNNPGGSATL 82

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 41.07 E-value: 3.06e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAV---STVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGG---RYNVQAnGDLEIQD-VTFSDAGKYTCYAQN 504
Cdd:cd04967     2 PVFEEQPDDTifpEDSDEKKVALNCRARANPVPSYRWLMNGTEIDLEsdyRYSLVD-GTLVISNpSKAKDAGHYQCLATN 80


                  ....*
gi 281360617  505 KFGEI 509
Cdd:cd04967    81 TVGSV 85

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 40.92 E-value: 3.54e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   54 PFIIECEADGQPEPEYSWIKNGKKFDWQAYDNRmlRQPGRGTLVIT----IPKDE-DRGHYQCFASNE-FGTATSnsvyv 127
Cdd:cd05722    18 PVVLNCSAESDPPPKIEWKKDGVLLNLVSDERR--QQLPNGSLLITsvvhSKHNKpDEGFYQCVAQNEsLGSIVS----- 90


                  ....*..
gi 281360617  128 RKAELNA 134
Cdd:cd05722    91 RTARVTV 97

Immunoglobulin (Ig)-like domain of NrCAM (Ng (neuronglia) CAM-related cell adhesion molecule); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of NrCAM (Ng (neuronglia) CAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409458 Cd Length: 95 Bit Score: 40.74 E-value: 3.58e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  354 EEVVFECRAAGVPEPKISWIHNGKPIEQSTpNPRRTVTDNT----IRIINLVKGDT--GNYGCNATNSLG 417
Cdd:cd05874    17 ENIVIQCEAKGKPPPSFSWTRNGTHFDIDK-DPKVTMKPNTgtlvINIMNGEKAEAyeGVYQCTARNERG 85

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 40.69 E-value: 3.74e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  143 LEAVEGEPFMLKCAAPdGFPSPTVNWMIQESIdgsIKSinNSRMTLDPEGNLWFSNVTREDASSdfyYACSATSVFRSEY 222
Cdd:cd20968     9 VTIIEGLKAVLPCTTM-GNPKPSVSWIKGDDL---IKE--NNRIAVLESGSLRIHNVQKEDAGQ---YRCVAKNSLGIAY 79

First immunoglobulin (Ig) domain of contactin-2; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-2-like. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. It may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module by contacts between IG domains 1 and 4, and domains 2 and 3. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-2 is also expressed in retinal amacrine cells in the developing chick retina, corresponding to the period of formation and maturation of AC processes. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409437 [Multi-domain] Cd Length: 97 Bit Score: 41.06 E-value: 3.76e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617   59 CEADGQPEPEYSWIKNGKKFDWqAYDNRMlRQPGrGTLVITIP-KDEDRGHYQCFASNEFGTATSNSVYVR 128
Cdd:cd05850    27 CRARASPPATYRWKMNGTELKM-EPDSRY-RLVA-GNLVISNPvKAKDAGSYQCLASNRRGTVVSREASLR 94

Third immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The third Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules, including vascular (VCAM), intercellular (ICAM), neural (NCAM) and mucosal addressin (MADCAM) cell adhesion molecules, as well as junction adhesion molecules (JAM).

Pssm-ID: 409569 Cd Length: 93 Bit Score: 40.84 E-value: 3.84e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  338 VPYFTKEPEIATAAeDEEVVFeCRAAGVPEPKISWIHNGKPIEQstpNPRRTVTDNT------IRIINLVKGDTGNYGCN 411
Cdd:cd20977     2 VPQYVSKDMMAKAG-DVTMIY-CMYGSNPTAHPNYFKNGKDVNG---NPEDRITRHNrtsgkrLLFKTTLPEDEGVYTCE 76

                          90
                  ....*....|
gi 281360617  412 ATNSLGYVYK 421
Cdd:cd20977    77 VDNGVGKPQK 86

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor (VEGFR); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor (VEGFR). The VEGFRs have an extracellular component with seven Ig-like domains, a transmembrane segment, and an intracellular tyrosine kinase domain interrupted by a kinase-insert domain. The VEGFR family consists of three members, VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), and VEGFR-3 (Flt-4). VEGFRs bind VEGFs with high affinity at the Ig-like domains. VEGF-A is important to the growth and maintenance of vascular endothelial cells and to the development of new blood- and lymphatic-vessels in physiological and pathological states. VEGFR-2 is a major mediator of the mitogenic, angiogenic, and microvascular permeability-enhancing effects of VEGF-A. VEGFR-1 may play an inhibitory part in these processes by binding VEGF and interfering with its interaction with VEGFR-2. VEGFR-1 has a signaling role in mediating monocyte chemotaxis. VEGFR-1 and VEGFR-2 may mediate a chemotactic and a survival signal in hematopoietic stem cells or leukemia cells. VEGFR-3 has been shown to be involved in tumor angiogenesis and growth. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409365 Cd Length: 90 Bit Score: 40.66 E-value: 3.85e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  343 KEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTpnprRTVTDNTIRIINLVKGDTGNYGCNATNSLGYVYKD 422
Cdd:cd04976     8 KQQVLEATAGKRSVRLPMKVKAYPPPEVVWYKDGLPLTEKA----RYLTRHSLIIKEVTEEDTGNYTILLSNKQSNVFKN 83


                  ...
gi 281360617  423 VYL 425
Cdd:cd04976    84 LTA 86

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 40.29 E-value: 3.94e-04

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617    615 PNAPK-LTGITCQADKAEIHWE--QQGDNRSPILHYTIQFNTsfTPASWDAAyeKVPNTDSSFVVQ-MSPWANYTFRVIA 690
Cdd:smart00060    1 PSPPSnLRVTDVTSTSVTLSWEppPDDGITGYIVGYRVEYRE--EGSEWKEV--NVTPSSTSYTLTgLKPGTEYEFRVRA 76


                    ....*..
gi 281360617    691 FNKIGAS 697
Cdd:smart00060   77 VNGAGEG 83

Immunoglobulin (Ig)-like domain at the C-terminus of semaphorins; The members here are composed of the immunoglobulin (Ig)-like domain in semaphorins. Semaphorins are transmembrane protein that have important roles in a variety of tissues. Functionally, semaphorins were initially characterized for their importance in the development of the nervous system and in axonal guidance. Later they have been found to be important for the formation and functioning of the cardiovascular, endocrine, gastrointestinal, hepatic, immune, musculoskeletal, renal, reproductive, and respiratory systems. Semaphorins function through binding to their receptors and transmembrane semaphorins also serves as receptors themselves. Although molecular mechanism of semaphorins is poorly understood, the Ig-like domains may be involved in ligand binding or dimerization.

Pssm-ID: 409368 Cd Length: 88 Bit Score: 40.52 E-value: 4.20e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617  342 TKEPEIATAAEDEEVVFECRAAGVPEpkiSWIHNGKPIEQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSL 416
Cdd:cd04979     2 SFKQISVKEGDTVILSCSVKSNNAPV---TWIHNGKKVPRYRSPRLVLKTERGLLIRSAQEADAGVYECHSGERV 73

Domain C2 of human cardiac Myosin Binding Protein C and similar domains; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) Domain C2 of human cardiac Myosin Binding Protein C (MyBP-C) and similar domains. MyBP-C is a thick filament protein involved in the regulation of muscle contraction. Mutations in cardiac MyBP-C gene are the second most frequent cause of hypertrophic cardiomyopathy. MyBP-C binds to myosin with two binding sites, one at its C-terminus and another at its N-terminus. The N-terminal binding site, consisting of immunoglobulin (lg) domains C1 and C2 connected by a flexible linker, interacts with the S2 segment of myosin in a phosphorylation-regulated manner. The C1 and C2 Ig domains can bind to and activate or inhibit the thin filament. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structures of the Ig domains of MyBP-C lack this strand and thus belong to the I-set of Ig superfamily domains. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors.

Pssm-ID: 409559 Cd Length: 82 Bit Score: 40.30 E-value: 4.33e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617  530 YEVAAGQSATFRCNEAHDDTleiEIDWWKDGQSIDFEAQPRFVKTN-DNSLTIAKTMELDSGEYTCVA 596
Cdd:cd20967     7 VQVSKGHKIRLTVELADPDA---EVKWYKDGQELQSSSKVIFESIGaKRTLTVQQASLADAGEYQCVA 71

C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein (also known as myomesin-2). Myomesin and M-protein are both structural proteins localized to the M-band, a transverse structure in the center of the sarcomere, and are candidates for M-band bridges. Both proteins are modular, consisting mainly of repetitive Ig-like and fibronectin type III (FnIII) domains. Myomesin is expressed in all types of vertebrate striated muscle; M-protein has a muscle-type specific expression pattern. Myomesin is present in both slow and fast fibers; M-protein is present only in fast fibers. It has been suggested that myomesin acts as a molecular spring with alternative splicing as a means of modifying its elasticity.

Pssm-ID: 319300 Cd Length: 92 Bit Score: 40.65 E-value: 4.35e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  259 LRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDR----ITQGHYGkSLVIRQTNFDDAGTYTCDVSNGVGNAQS 328
Cdd:cd05737    14 MEGKTLNLTCNVWGDPPPEVSWLKNDQALAFLDHcnlkVEAGRTV-YFTINGVSSEDSGKYGLVVKNKYGSETS 86

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 40.69 E-value: 4.43e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617   56 IIECEADGQPEPEYSWIKNGKKFdwQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTA 120
Cdd:cd05730    22 TLACDADGFPEPTMTWTKDGEPI--ESGEEKYSFNEDGSEMTILDVDKLDEAEYTCIAENKAGEQ 84

Immunoglobulin (Ig)-like domain of human titin C terminus and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain from the C-terminus of human titin x and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is gigantic; depending on isoform composition it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone and appears to function similar to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 143224 [Multi-domain] Cd Length: 92 Bit Score: 40.42 E-value: 4.49e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  251 VSRRQSLAL-RGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDR--ITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQ 327
Cdd:cd05747     7 LTKPRSLTVsEGESARFSCDVDGEPAPTVTWMREGQIIVSSQRhqITSTEYKSTFEISKVQMSDEGNYTVVVENSEGKQE 86


                  ....*
gi 281360617  328 S-FSI 331
Cdd:cd05747    87 AqFTL 91

Immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409397 [Multi-domain] Cd Length: 97 Bit Score: 40.55 E-value: 4.61e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  261 GKRMELFCIYGGTPLPQTVW--SKDG-----QRIQWSDRITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQSFSIIL 333
Cdd:cd05734    16 GKAVVLNCSADGYPPPTIVWkhSKGSgvpqfQHIVPLNGRIQLLSNGSLLIKHVLEEDSGYYLCKVSNDVGADISKSMYL 95


                  ..
gi 281360617  334 NV 335
Cdd:cd05734    96 TV 97

Sixth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the sixth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409551 Cd Length: 94 Bit Score: 40.55 E-value: 4.65e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  533 AAGQSATFRCNEAHDDtLEIEIDWWKDGQSI--DFEAQPRFVKTNDNSLTIAKTMELDSGEYTCVARTRLDEATARANLI 610
Cdd:cd20959    15 QVGMRAQLHCGVPGGD-LPLNIRWTLDGQPIsdDLGITVSRLGRRSSILSIDSLEASHAGNYTCHARNSAGSASYTAPLT 93


                  .
gi 281360617  611 V 611
Cdd:cd20959    94 V 94

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 40.62 E-value: 4.71e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  446 GRNVTIKCRVNGSPKPLVKWLRASNWL-TGGRYN----VQANGD----LEIQDVTFSDAGKYTCYAQNKFGEIQ 510
Cdd:cd20956    16 GPSVSLKCVASGNPLPQITWTLDGFPIpESPRFRvgdyVTSDGDvvsyVNISSVRVEDGGEYTCTATNDVGSVS 89

Fifth domain (immunoglobulin-like) of Trk receptors TrkA, TrkB, and TrkC; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth domain of Trk receptors TrkA, TrkB, and TrkC, an immunoglobulin (Ig)-like domain which binds to neurotrophin. The Trk family of receptors are tyrosine kinase receptors. They are activated by dimerization, leading to autophosphorylation of intracellular tyrosine residues, and triggering the signal transduction pathway. TrkA, TrkB, and TrkC share significant sequence homology and domain organization. The first three domains are leucine-rich domains while the fourth and fifth domains are Ig-like domains playing a part in ligand binding. TrkA, TrkB, and TrkC mediate the trophic effects of the neurotrophin Nerve Growth Factor (NGF) family. TrkA is recognized by NGF. TrkB is recognized by brain-derived neurotrophic factor (BDNF) and neurotrophin (NT)-4. TrkC is recognized by NT-3. NT-3 is promiscuous as in some cell systems it activates TrkA and TrkB receptors. TrkA is a receptor found in all major NGF targets, including the sympathetic, trigeminal, and dorsal root ganglia, cholinergic neurons of the basal forebrain, and the striatum. TrKB transcripts are found throughout multiple structures of the central and peripheral nervous systems. The TrkC gene is expressed throughout the mammalian nervous system. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409360 Cd Length: 96 Bit Score: 40.46 E-value: 4.93e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617   57 IECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQPGR------GTLVITIPKDEDRGHYQCFASNEFGTATSN 123
Cdd:cd04971    18 IPFTVRGNPKPTLTWYHNGAVLNESDYIRTEIHYEAAtpteyhGCLKFDNPTHVNNGNYTLVASNEYGQDSKS 90

Second immunoglobulin (Ig)-like domain of Axl/Tyro3 family receptor tyrosine kinases (RTKs); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in the Axl/Tyro3 family of receptor tyrosine kinases (RTKs). This family includes Axl (also known as Ark, Ufo, and Tyro7), Tyro3 (also known as Sky, Rse, Brt, Dtk, and Tif), and Mer (also known as Nyk, c-Eyk, and Tyro12). Axl/Tyro3 family receptors have an extracellular portion with two Ig-like domains followed by two fibronectin-types III (FNIII) domains, a membrane-spanning single helix, and a cytoplasmic tyrosine kinase domain. Axl, Tyro3, and Mer are widely expressed in adult tissues, though they show higher expression in the brain, lymphatic and vascular systems, and testis. Axl, Tyro3, and Mer bind the vitamin K dependent protein Gas6 with high affinity, and in doing so activate their tyrosine kinase activity. Axl/Gas6 signaling may play a part in cell adhesion processes, prevention of apoptosis, and cell proliferation.

Pssm-ID: 409407 Cd Length: 82 Bit Score: 40.14 E-value: 4.94e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  340 YFTKEPEIATAAEDEEVVFECRAAGVPEP-KISWIHNGKPIEQSTPNPRRTVTdntiriinlVKG--DTGNYGCNATNSL 416
Cdd:cd05749     1 HFTVEPEDLAVTANTPFNLTCQAVGPPEPvEILWWQGGSPLGGPPAPSPSVLN---------VPGlnETTKFSCEAHNAK 71


                  .
gi 281360617  417 G 417
Cdd:cd05749    72 G 72

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 39.92 E-value: 4.98e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617   59 CEADGQPEPEYSWIKNGKKFdwqAYDNRMLRQpGRGTLVITIPKDEDRGHYQCFASNEFGT 119
Cdd:cd05745     9 CEAQGYPQPVIAWTKGGSQL---SVDRRHLVL-SSGTLRISRVALHDQGQYECQAVNIVGS 65

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 40.15 E-value: 5.25e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  523 ITQEPQNYEVAAGQSATFRCNEAHDDtlEIEIDW-WKDGQSIDFEAqpRFVKTNDNSLTIAKTMELDSGEYTCVARTRLD 601
Cdd:cd05764     3 ITRHTHELRVLEGQRATLRCKARGDP--EPAIHWiSPEGKLISNSS--RTLVYDNGTLDILITTVKDTGAFTCIASNPAG 78

                          90
                  ....*....|
gi 281360617  602 EATARANLIV 611
Cdd:cd05764    79 EATARVELHI 88

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 39.47 E-value: 5.26e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  264 MELFCIYGGTPLPQTVWSKDGQRIQWSDRITQGHYGkSLVIRQTNFDDAGTYTCDVSNGVGNAqSFSIIL 333
Cdd:cd05746     1 VQIPCSAQGDPEPTITWNKDGVQVTESGKFHISPEG-YLAIRDVGVADQGRYECVARNTIGYA-SVSMVL 68

Fourth immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues, and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409388 Cd Length: 84 Bit Score: 40.26 E-value: 5.28e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617   56 IIECEADGQPEPEYSWIKNGKKFDWQAYdnrmLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNS 124
Cdd:cd05723    16 VFECEVTGKPTPTVKWVKNGDVVIPSDY----FKIVKEHNLQVLGLVKSDEGFYQCIAENDVGNAQASA 80

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 409395 [Multi-domain] Cd Length: 96 Bit Score: 40.59 E-value: 5.41e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617  258 ALRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDR------ITQGHYGKS-LVIRQTNFDDAGTYTCDVSNGVGNAQ 327
Cdd:cd05732    13 AVELEQITLTCEAEGDPIPEITWRRATRGISFEEGdldgriVVRGHARVSsLTLKDVQLTDAGRYDCEASNRIGGDQ 89

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 39.91 E-value: 5.55e-04

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617    817 DAPTNFTMRQITSsTSGYMAWTPVSEESVRGHFKGYKIQTWTENEGEEglrEIHVKGDTHNALVTQFKPDSKNYARILAY 896
Cdd:smart00060    2 SPPSNLRVTDVTS-TSVTLSWEPPPDDGITGYIVGYRVEYREEGSEWK---EVNVTPSSTSYTLTGLKPGTEYEFRVRAV 77


                    ....*.
gi 281360617    897 NGRFNG 902
Cdd:smart00060   78 NGAGEG 83

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule 1(NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM) and heterophilic (NCAM-non-NCAM) interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143277 [Multi-domain] Cd Length: 97 Bit Score: 40.35 E-value: 6.01e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  346 EIATAAE-DEEVVFECRAAGVPEPKISWIHNGKPI-EQSTPNPRRTVTDNTIRIINLV-----KGDTGNYGCNATNSLGY 418
Cdd:cd05869     9 ENQTAMElEEQITLTCEASGDPIPSITWRTSTRNIsSEEKTLDGHIVVRSHARVSSLTlkyiqYTDAGEYLCTASNTIGQ 88


                  ....*....
gi 281360617  419 VYKDVYLNV 427
Cdd:cd05869    89 DSQSMYLEV 97

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 39.84 E-value: 6.14e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  258 ALRGKRMELFCIYGGTPLPQTVWSK-DGQRI-QWSDRITQGhygkSLVIRQTNFDDAGTYTCDVSNGVG 324
Cdd:cd04968    13 ALKGQTVTLECFALGNPVPQIKWRKvDGSPSsQWEITTSEP----VLEIPNVQFEDEGTYECEAENSRG 77

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three IG-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans.

Pssm-ID: 409443 [Multi-domain] Cd Length: 95 Bit Score: 40.22 E-value: 6.14e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617   59 CEADGQPEPEYSWIKNGKKFdwqAYDNRM----LRQPgRGTLVITIPKDEDRGHYQCFASNEFGT 119
Cdd:cd05857    26 CPAAGNPTPTMRWLKNGKEF---KQEHRIggykVRNQ-HWSLIMESVVPSDKGNYTCVVENEYGS 86

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 39.93 E-value: 6.18e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  527 PQNYEVAAGQSATFRCneAHDDTLEIEIDWWKDGQSIDFEAQPRFVKTNDNSLTIAKTMELDSGEYTCVARTRLDEATAR 606
Cdd:cd20976     8 PKDLEAVEGQDFVAQC--SARGKPVPRITWIRNAQPLQYAADRSTCEAGVGELHIQDVLPEDHGTYTCLAKNAAGQVSCS 85


                  ....*
gi 281360617  607 ANLIV 611
Cdd:cd20976    86 AWVTV 90

C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein (also known as myomesin-2). Myomesin and M-protein are both structural proteins localized to the M-band, a transverse structure in the center of the sarcomere, and are candidates for M-band bridges. Both proteins are modular, consisting mainly of repetitive Ig-like and fibronectin type III (FnIII) domains. Myomesin is expressed in all types of vertebrate striated muscle; M-protein has a muscle-type specific expression pattern. Myomesin is present in both slow and fast fibers; M-protein is present only in fast fibers. It has been suggested that myomesin acts as a molecular spring with alternative splicing as a means of modifying its elasticity.

Pssm-ID: 319300 Cd Length: 92 Bit Score: 39.88 E-value: 6.81e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617   59 CEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSN 123
Cdd:cd05737    23 CNVWGDPPPEVSWLKNDQALAFLDHCNLKVEAGRTVYFTINGVSSEDSGKYGLVVKNKYGSETSD 87

Eighth immunoglobulin (Ig)-like domain of human myosin light-chain kinase (MLCK) and similar protein; member of the I-set of IgSF domains; The members here are composed of the eighth immunoglobulin (Ig)-like domain of human myosin light-chain kinase (MLCK) and similar proteins. Myosin light-chain kinase (MLCK) is a key regulator of different forms of cell motility involving actin and myosin II. Agonist stimulation of smooth muscle cells increases cytosolic Ca2+ which binds calmodulin. This Ca2+-calmodulin complex in turn binds to and activates MLCK. Activated MLCK leads to the phosphorylation of the 20 kDa myosin regulatory light chain (RLC) of myosin II and the stimulation of actin-activated myosin MgATPase activity. MLCK is widely present in vertebrate tissues; it phosphorylates the 20 kDa RLC of both smooth and nonmuscle myosin II. Phosphorylation leads to the activation of the myosin motor domain and altered structural properties of myosin II. In smooth muscle MLCK it is involved in initiating contraction. In nonmuscle cells, MLCK may participate in cell division and cell motility; it has been suggested MLCK plays a role in cardiomyocyte differentiation and contraction through regulation of nonmuscle myosin II.

Pssm-ID: 409419 Cd Length: 99 Bit Score: 40.32 E-value: 6.93e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  522 RITQEPQNYEVAAGQSATFRCNEAhdDTLEIEIDWWKDGQSIDfEAQPRFVKTNDNS--LTIAKTMELDSGEYTCVARTR 599
Cdd:cd05762     3 QIIQFPEDMKVRAGESVELFCKVT--GTQPITCTWMKFRKQIQ-EGEGIKIENTENSskLTITEGQQEHCGCYTLEVENK 79

                          90
                  ....*....|....*....
gi 281360617  600 LDEATARANLIVQDVPNAP 618
Cdd:cd05762    80 LGSRQAQVNLTVVDKPDPP 98

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 39.91 E-value: 8.17e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  524 TQEPQNYEVAAGQSATFRCN-EAHDDTleiEIDWWKDGqSIDFEA--QPRF-VKTNDNSLTIAKTMELDSGEYTCVARTR 599
Cdd:cd05763     3 TKTPHDITIRAGSTARLECAaTGHPTP---QIAWQKDG-GTDFPAarERRMhVMPEDDVFFIVDVKIEDTGVYSCTAQNS 78

                          90
                  ....*....|..
gi 281360617  600 LDEATARANLIV 611
Cdd:cd05763    79 AGSISANATLTV 90

First immunoglobulin (Ig) domain of contactin-2; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-2-like. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. It may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module by contacts between IG domains 1 and 4, and domains 2 and 3. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-2 is also expressed in retinal amacrine cells in the developing chick retina, corresponding to the period of formation and maturation of AC processes. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409437 [Multi-domain] Cd Length: 97 Bit Score: 39.91 E-value: 8.62e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAE---DEEVVFECRAAGVPEPKISWIHNGKPIEQStPNPRRTVTDNTIRIINLVKG-DTGNYGCNATN 414
Cdd:cd05850     3 PVFEEQPSSTLFPEgsaEEKVTLACRARASPPATYRWKMNGTELKME-PDSRYRLVAGNLVISNPVKAkDAGSYQCLASN 81


                  ....*
gi 281360617  415 SLGYV 419
Cdd:cd05850    82 RRGTV 86

Immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains NrCAM [Ng(neuronglia)CAM-related cell adhesion molecule], which is primarily expressed in the nervous system, and human neurofascin. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409396 [Multi-domain] Cd Length: 94 Bit Score: 39.70 E-value: 8.78e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  353 DEEVVFECRAAGVPEPKISWIHNGKPIEQSTpNPRRTVTDN----TIRIINLVKGD-TGNYGCNATNSLG 417
Cdd:cd05733    16 RDNITIKCEAKGNPQPTFRWTKDGKFFDPAK-DPRVSMRRRsgtlVIDNHNGGPEDyQGEYQCYASNELG 84

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 39.23 E-value: 8.87e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617  151 FMLKCAAPdGFPSPTVNWMIQESIDGSikSINNSRMTLDPEGNLWFSNVTREDASSdfyYACSAT 215
Cdd:cd00096     1 VTLTCSAS-GNPPPTITWYKNGKPLPP--SSRDSRRSELGNGTLTISNVTLEDSGT---YTCVAS 59

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 39.85 E-value: 8.88e-04

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  360 CRAAGVPEPKISWIHNGKPIEQstpNPRRTVTDNTIR---------IINLVKGDTGNYGCNATNSLGYV 419
Cdd:cd20956    23 CVASGNPLPQITWTLDGFPIPE---SPRFRVGDYVTSdgdvvsyvnISSVRVEDGGEYTCTATNDVGSV 88

First Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409566 [Multi-domain] Cd Length: 93 Bit Score: 39.64 E-value: 9.13e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQST-PNPRRTVTDNTIR--IINLVKGDTGNYGCNATNS 415
Cdd:cd20974     1 PVFTQPLQSVVVLEGSTATFEAHVSGKPVPEVSWFRDGQVISTSTlPGVQISFSDGRAKlsIPAVTKANSGRYSLTATNG 80

                          90
                  ....*....|..
gi 281360617  416 LGYVYKDVYLNV 427
Cdd:cd20974    81 SGQATSTAELLV 92

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 39.30 E-value: 9.47e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   344 EPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPNPRRTVTdntiriinlvKGDTGNYGCNATNS-LGYVYKD 422
Cdd:pfam13895    5 TPSPTVVTEGEPVTLTCSAPGNPPPSYTWYKDGSAISSSPNFFTLSVS----------AEDSGTYTCVARNGrGGKVSNP 74


                   ....*
gi 281360617   423 VYLNV 427
Cdd:pfam13895   75 VELTV 79

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 39.44 E-value: 9.54e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617  440 AVSTVD-GRNVTIKCRVNGSPKPLVKWLRASNWLT-GGRYNVQANGDLEIQDVTFSDAGKYTCYAQNKFGEIQADGSL 515
Cdd:cd20957     9 PVQTVDfGRTAVFNCSVTGNPIHTVLWMKDGKPLGhSSRVQILSEDVLVIPSVKREDKGMYQCFVRNDGDSAQATAEL 86

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 39.09 E-value: 9.58e-04

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  356 VVFECRAAGVPEPKISWIHNGKPIEQStpNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLGYVYKDVYL 425
Cdd:cd05746     1 VQIPCSAQGDPEPTITWNKDGVQVTES--GKFHISPEGYLAIRDVGVADQGRYECVARNTIGYASVSMVL 68

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor (VEGFR); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor (VEGFR). The VEGFRs have an extracellular component with seven Ig-like domains, a transmembrane segment, and an intracellular tyrosine kinase domain interrupted by a kinase-insert domain. The VEGFR family consists of three members, VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), and VEGFR-3 (Flt-4). VEGFRs bind VEGFs with high affinity at the Ig-like domains. VEGF-A is important to the growth and maintenance of vascular endothelial cells and to the development of new blood- and lymphatic-vessels in physiological and pathological states. VEGFR-2 is a major mediator of the mitogenic, angiogenic, and microvascular permeability-enhancing effects of VEGF-A. VEGFR-1 may play an inhibitory part in these processes by binding VEGF and interfering with its interaction with VEGFR-2. VEGFR-1 has a signaling role in mediating monocyte chemotaxis. VEGFR-1 and VEGFR-2 may mediate a chemotactic and a survival signal in hematopoietic stem cells or leukemia cells. VEGFR-3 has been shown to be involved in tumor angiogenesis and growth. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409365 Cd Length: 90 Bit Score: 39.50 E-value: 9.64e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  252 SRRQSL--ALRGKR-MELFCIYGGTPLPQTVWSKDGQRIQWSDRITQGHygkSLVIRQTNFDDAGTYTCDVSNGVGNA-Q 327
Cdd:cd04976     6 HRKQQVleATAGKRsVRLPMKVKAYPPPEVVWYKDGLPLTEKARYLTRH---SLIIKEVTEEDTGNYTILLSNKQSNVfK 82


                  ....*...
gi 281360617  328 SFSIILNV 335
Cdd:cd04976    83 NLTATLVV 90

First immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The first Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules, including vascular (VCAM), intercellular (ICAM), neural (NCAM) and mucosal addressin (MADCAM) cell adhesion molecules, as well as junction adhesion molecules (JAM).

Pssm-ID: 409571 Cd Length: 91 Bit Score: 39.48 E-value: 1.01e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617  535 GQSATFRCNEAHDDTlEIEIDWWKDGQSIDFEAQPRFVKTNDNSLTIAKTMELDSGEYTCVARTRLDEATARA 607
Cdd:cd20979    15 GQPTVLECVTEGGDQ-GVKYSWLKDGKSFNWQEHNVAQRKDEGSLVFLKPQASDEGQYQCFAETPAGVASSRV 86

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 39.40 E-value: 1.04e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  524 TQEPQNYEVAAGQSATFRCNEAHDDTLEIEidWWKDGQSIDFEAQPRFVKTND--NSLTIAKTMELDSGEYTCVARTRLD 601
Cdd:cd05744     4 LQAPGDLEVQEGRLCRFDCKVSGLPTPDLF--WQLNGKPVRPDSAHKMLVRENgrHSLIIEPVTKRDAGIYTCIARNRAG 81

                          90
                  ....*....|
gi 281360617  602 EATARANLIV 611
Cdd:cd05744    82 ENSFNAELVV 91

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 39.01 E-value: 1.07e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  446 GRNVTIKCRVNGSPKPLVKW----------LRASNWLTGGRynvqanGDLEIQDVTFSDAGKYTCYAQNKFGEI--QADG 513
Cdd:cd05743     1 GETVEFTCVATGVPTPIINWrlnwghvpdsARVSITSEGGY------GTLTIRDVKESDQGAYTCEAINTRGMVfgIPDG 74


                  ....
gi 281360617  514 SLVV 517
Cdd:cd05743    75 ILTV 78

First Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409566 [Multi-domain] Cd Length: 93 Bit Score: 39.64 E-value: 1.09e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  432 PTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLR---ASNWLTGGRYNVQANGD---LEIQDVTFSDAGKYTCYAQNK 505
Cdd:cd20974     1 PVFTQPLQSVVVLEGSTATFEAHVSGKPVPEVSWFRdgqVISTSTLPGVQISFSDGrakLSIPAVTKANSGRYSLTATNG 80

                          90
                  ....*....|...
gi 281360617  506 FGEIQADGSLVVK 518
Cdd:cd20974    81 SGQATSTAELLVL 93

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 39.54 E-value: 1.15e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  445 DGRNVTIKCRVNGSPKPLVKWLRASNWL---TGGRYNVqANGDLEIQDVT-FSDAGKYTCYAQNKFGEI 509
Cdd:cd05848    18 DEKKVILNCEARGNPVPTYRWLRNGTEIdteSDYRYSL-IDGNLIISNPSeVKDSGRYQCLATNSIGSI 85

Second Ig-like domain of Junctional adhesion molecule-1 (JAM1); a member of the I-set of IgSF domains; The members here are composed of the second Ig-like domain of Junctional adhesion molecule-1 (JAM1). JAM1 is an immunoglobulin superfamily (IgSF) protein with two Ig-like domains in its extracellular region; it plays a role in the formation of endothelial and epithelial tight junction and acts as a receptor for mammalian reovirus sigma-1. The IgSF is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The second Ig-like domain of JAM1 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, the A strand of the I-set is discontinuous but lacks a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors.

Pssm-ID: 409542 Cd Length: 97 Bit Score: 39.61 E-value: 1.18e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   56 IIEC-EADGQPEPEYSWIKNG-------KKFdwQAYDNRMLR-QPGRGTLVITIPKDEDRGHYQCFASNEFGTA-TSNSV 125
Cdd:cd20950    16 VLTCsEPDGSPPSEYTWFKDGvvmptnpKST--RAFSNSSYSlDPTTGELVFDPLSASDTGEYSCEARNGYGTPmRSNAV 93

First C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409474 Cd Length: 92 Bit Score: 39.31 E-value: 1.22e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  339 PYFTKEPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPIEQSTPN---PRRTVTDNTIRIINLVKGDTGNYGCNATNS 415
Cdd:cd05893     1 PFFEMKLKHYKIFEGMPVTFTCRVAGNPKPKIYWFKDGKQISPKSDHytiQRDLDGTCSLHTTASTLDDDGNYTIMAANP 80


                  ....
gi 281360617  416 LGYV 419
Cdd:cd05893    81 QGRI 84

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 143259 Cd Length: 88 Bit Score: 38.85 E-value: 1.40e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617  251 VSRRQSLALRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDRITQGhyGKSLVIRQTNFDDAGTYTCDVSN 321
Cdd:cd05851     6 VKFKDTYALKGQNVTLECFALGNPVPVIRWRKILEPMPATAEISMS--GAVLKIFNIQPEDEGTYECEAEN 74

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 38.53 E-value: 1.42e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617   432 PTISEAPAAVStvDGRNVTIKCRVNGSPKPLVKWLRASNWLTGgrynvqaNGDLEIQDVTFSDAGKYTCYAQN 504
Cdd:pfam13895    2 PVLTPSPTVVT--EGEPVTLTCSAPGNPPPSYTWYKDGSAISS-------SPNFFTLSVSAEDSGTYTCVARN 65

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 39.03 E-value: 1.44e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617  261 GKRMELFC-IYGGTPLPQTVWSKDGQRIQWSD----RITQGHYGKSLVIRQTNFDDAGTYTCDVSNGVGNAQS 328
Cdd:cd05750    14 GSKLVLKCeATSENPSPRYRWFKDGKELNRKRpkniKIRNKKKNSELQINKAKLEDSGEYTCVVENILGKDTV 86

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 143259 Cd Length: 88 Bit Score: 38.85 E-value: 1.56e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  431 PPTISEAPAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQANGDLEIQDVTFSDAGKYTCYAQN 504
Cdd:cd05851     1 PADINVKFKDTYALKGQNVTLECFALGNPVPVIRWRKILEPMPATAEISMSGAVLKIFNIQPEDEGTYECEAEN 74

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 143259 Cd Length: 88 Bit Score: 38.85 E-value: 1.57e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  350 AAEDEEVVFECRAAGVPEPKISWihnGKPIEQSTPNPRRTVTDNTIRIINLVKGDTGNYGCNATNSLGYVYKDVYLNVQ 428
Cdd:cd05851    13 ALKGQNVTLECFALGNPVPVIRW---RKILEPMPATAEISMSGAVLKIFNIQPEDEGTYECEAENIKGKDKHQARVYVQ 88

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 38.85 E-value: 1.58e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617   57 IECEADGQPEPEYSWIKNGKKFDWQAYDNRMLRQPGRGtLVITIPKDEDRGHYQCFASNEFGTAT 121
Cdd:cd20949    19 ILCEVKGEPQPNVTWHFNGQPISASVADMSKYRILADG-LLINKVTQDDTGEYTCRAYQVNSIAS 82

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 38.83 E-value: 1.66e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617  145 AVEGEPFMLKCAApDGFPSPTVNW-MIQESIDGSIKSI-NNSRMTLDPEGNLWFSNVTREDassDFYYACSAT 215
Cdd:cd20954    13 VAAGQDVMLHCQA-DGFPTPTVTWkKATGSTPGEYKDLlYDPNVRILPNGTLVFGHVQKEN---EGHYLCEAK 81

First immunoglobulin (Ig)-like domain of Fcgamma-receptors (FcgammaRs), and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain of Fcgamma-receptors (FcgammaRs). Interactions between IgG and FcgammaR are important to the initiation of cellular and humoral response. IgG binding to FcgammaR leads to a cascade of signals and ultimately to functions such as antibody-dependent-cellular-cytotoxicity (ADCC), endocytosis, phagocytosis, release of inflammatory mediators, etc. FcgammaR has two Ig-like domains. This group also contains FcepsilonRI which binds IgE with high affinity.

Pssm-ID: 409410 [Multi-domain] Cd Length: 79 Bit Score: 38.50 E-value: 1.73e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  446 GRNVTIKCRVNGSPKPL-VKWLRASNWLtggryNVQANgDLEIQDVTFSDAGKYTCYAQN 504
Cdd:cd05752    15 GEKVTLTCQGFYSPEQNsTQWYHNGTLI-----SSTSS-SYRIVAATVNDSGEYRCQTQG 68

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 38.24 E-value: 1.80e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617  261 GKRMELFCIYGGTPLPQTVWskdgqRIQW-----SDRITQGHYGK--SLVIRQTNFDDAGTYTCDVSNGVG 324
Cdd:cd05743     1 GETVEFTCVATGVPTPIINW-----RLNWghvpdSARVSITSEGGygTLTIRDVKESDQGAYTCEAINTRG 66

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule 1(NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM) and heterophilic (NCAM-non-NCAM) interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143277 [Multi-domain] Cd Length: 97 Bit Score: 38.81 E-value: 2.09e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617  449 VTIKCRVNGSPKPLVKWLRASNWLTG------GRYNVQAN---GDLEIQDVTFSDAGKYTCYAQNKFG-EIQA 511
Cdd:cd05869    20 ITLTCEASGDPIPSITWRTSTRNISSeektldGHIVVRSHarvSSLTLKYIQYTDAGEYLCTASNTIGqDSQS 92

Immunoglobulin (Ig)-like domain of human carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) domains 2, 4, and 6, and similar domains; The members here are composed of the second, fourth, and sixth immunoglobulin (Ig)-like domains in human carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) protein subfamily. The CEA family is a group of anchored or secreted glycoproteins expressed by epithelial cells, leukocytes, endothelial cells, and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. This group represents the CEACAM subfamily. CEACAM1 has many important cellular functions; it is a cell adhesion molecule and a signaling molecule that regulates the growth of tumor cells, an angiogenic factor, and a receptor for bacterial and viral pathogens, including mouse hepatitis virus (MHV). In mice, four isoforms of CEACAM1 generated by alternative splicing have either two [D1, D4] or four [D1-D4] Ig-like domains on the cell surface.

Pssm-ID: 409402 [Multi-domain] Cd Length: 89 Bit Score: 38.14 E-value: 2.62e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617   50 ESDNPFIIECEADGQPEpEYSWIKNGKkfDWQAYDnRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTATSNSV 125
Cdd:cd05740    13 EDKDAVTLTCEPETQNT-SYLWWFNGQ--SLPVTP-RLTLSNGNRTLTLLNVTREDAGAYQCEISNPVSANRSDPV 84

Domain C2 of human cardiac Myosin Binding Protein C and similar domains; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) Domain C2 of human cardiac Myosin Binding Protein C (MyBP-C) and similar domains. MyBP-C is a thick filament protein involved in the regulation of muscle contraction. Mutations in cardiac MyBP-C gene are the second most frequent cause of hypertrophic cardiomyopathy. MyBP-C binds to myosin with two binding sites, one at its C-terminus and another at its N-terminus. The N-terminal binding site, consisting of immunoglobulin (lg) domains C1 and C2 connected by a flexible linker, interacts with the S2 segment of myosin in a phosphorylation-regulated manner. The C1 and C2 Ig domains can bind to and activate or inhibit the thin filament. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structures of the Ig domains of MyBP-C lack this strand and thus belong to the I-set of Ig superfamily domains. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors.

Pssm-ID: 409559 Cd Length: 82 Bit Score: 37.99 E-value: 2.63e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617  261 GKRMELFCIYGGTPLPQTvWSKDGQRIQWSDRITQGHYG--KSLVIRQTNFDDAGTYTCDV 319
Cdd:cd20967    12 GHKIRLTVELADPDAEVK-WYKDGQELQSSSKVIFESIGakRTLTVQQASLADAGEYQCVA 71

Second immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structures of this group show that the second Ig domain lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules, including vascular (VCAM), intercellular (ICAM), neural (NCAM) and mucosal addressin (MADCAM) cell adhesion molecules, as well as junction adhesion molecules (JAM).

Pssm-ID: 409557 Cd Length: 101 Bit Score: 38.38 E-value: 2.80e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  441 VSTVDGRNVTIKCRV-NGSPKPLVKWLRA-------SNWLTGGRYNVQANGDLEIQDVT---FSDAGKYTCYAQNKfgei 509
Cdd:cd20965    12 KKPVEGKPFKLDCNVpPGYPKPTIEWKKQlvsdsskADTILDRRITISPNGDLYFTNVTkedVSTDYKYVCVAKTP---- 87

                          90
                  ....*....|..
gi 281360617  510 QADGSLVVKEHT 521
Cdd:cd20965    88 AVDGEVILVEYI 99

CD80-like C2-set immunoglobulin domain; These domains belong to the immunoglobulin superfamily.

Pssm-ID: 400489 Cd Length: 89 Bit Score: 38.17 E-value: 3.25e-03

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|..
gi 281360617   344 EPEIAT-AAEDEEVVFECRAA-GVPEPKISWIHNGKPIEQST 383
Cdd:pfam08205    4 EPPASLlEGEGPEVVATCSSAgGKPAPRITWYLDGKPLEAAE 45

Fifth immunoglobulin (Ig)-like domain of the carcinoembryonic antigen (CEA) related cell adhesion molecule 5 (CEACAM5) and similar domains; member of the C2-set IgSF domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain of the carcinoembryonic antigen (CEA) related cell adhesion molecule 5 (CEACAM5) and similar domains. The CEA family is a group of anchored or secreted glycoproteins, expressed by epithelial cells, leukocytes, endothelial cells and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), also known as CD66e (Cluster of Differentiation 66e), is a cell surface glycoprotein that plays a role in cell adhesion, intracellular signaling and tumor progression. Diseases associated with CEACAM5 include lung cancer and rectum cancer. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409540 Cd Length: 76 Bit Score: 37.48 E-value: 3.27e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  344 EPEIATAAEDEEVVFECRAAGVPEPKISWIHNGKPiEQSTpnprrtvtdNTIRIINLVKGDTGNYGCNATNSLG 417
Cdd:cd20948     1 SPSDTYYLSGENLNLSCHAASNPPAQYSWTINGTF-QTSS---------QELFLPAITENNEGTYTCSAHNSLT 64

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 37.99 E-value: 3.50e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  245 PPVRQYVSRRQSLALRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSD-RITQGHYGKSLVIRQTNFDDAGTYTCDVSNGV 323
Cdd:cd05730     2 PTIRARQSEVNATANLGQSVTLACDADGFPEPTMTWTKDGEPIESGEeKYSFNEDGSEMTILDVDKLDEAEYTCIAENKA 81

                          90
                  ....*....|..
gi 281360617  324 GNAQSfSIILNV 335
Cdd:cd05730    82 GEQEA-EIHLKV 92

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 37.58 E-value: 3.56e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617   54 PFIIECEADGQPEPEYSWikngKKFDWQAYDNRMLRQPGRGTLVITIPKDEDRGHYQCFASNEFGTA 120
Cdd:cd05876    12 SLVLECIAEGLPTPTVKW----LRPSGPLPPDRVKYQNHNKTLQLLNVGESDDGEYVCLAENSLGSA 74

C5 immunoglobulin (Ig) domain of cardiac myosin binding protein C (MyBP-C); The members here are composed of the C5 immunoglobulin (Ig) domain of cardiac myosin binding protein C (MyBP-C). MyBP-C consists of repeated domains, Ig and fibronectin type 3, and various linkers. Three isoforms of MYBP-C exist: slow-skeletal (ssMyBP-C), fast-skeletal (fsMyBP-C), and cardiac (cMyBP-C). cMYBP-C has insertions between and inside domains and an additional cardiac-specific Ig domain at the N-terminus. For cMYBP_C an interaction has been demonstrated between this C5 domain and the Ig C8 domain.

Pssm-ID: 409475 Cd Length: 86 Bit Score: 37.90 E-value: 3.61e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  437 APAAVSTVDGRNVTIKCRVNGSPKPLVKWLRASNWLTG--GRYNVQANGDLE---IQDVTFSDAGKYTCYAQNKFGEIQA 511
Cdd:cd05894     1 AENTIVVVAGNKLRLDVPISGEPAPTVTWSRGDKAFTAteGRVRVESYKDLSsfvIEGAEREDEGVYTITVTNPVGEDHA 80


                  ....*..
gi 281360617  512 dgSLVVK 518
Cdd:cd05894    81 --SLFVK 85

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 37.81 E-value: 4.19e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  434 ISEAPAAVSTvDGRNVTIKCRVNGSPKPLVKWLRASNWLTGGRYNVQANGD---LEIQDVTFSDAGKYTCYAQNKFGEIQ 510
Cdd:cd04978     3 IIEPPSLVLS-PGETGELICEAEGNPQPTITWRLNGVPIEPAPEDMRRTVDgrtLIFSNLQPNDTAVYQCNASNVHGYLL 81


                  ....*..
gi 281360617  511 ADGSLVV 517
Cdd:cd04978    82 ANAFLHV 88

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 2 (NCAM-2); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule NCAM-2 (also known as OCAM/mamFas II and RNCAM). NCAM-2 is organized similarly to NCAM, including five N-terminal Ig-like domains and two fibronectin type III domains. NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE), and may function like NCAM, as an adhesion molecule. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143278 [Multi-domain] Cd Length: 98 Bit Score: 38.03 E-value: 4.20e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  249 QYVSRRQSLALRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSD-------RI-TQGHYGKS-LVIRQTNFDDAGTYTCDV 319
Cdd:cd05870     4 HIIQLKNETTVENGAATLSCKAEGEPIPEITWKRASDGHTFSEgdkspdgRIeVKGQHGESsLHIKDVKLSDSGRYDCEA 83

                          90
                  ....*....|....*.
gi 281360617  320 SNGVGNAQSfSIILNV 335
Cdd:cd05870    84 ASRIGGHQK-SMYLDI 98

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 37.86 E-value: 4.28e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617 1041 FRINW-LPSTEGHPGTHFFTMHRIKGETQWIRENEEKNSDYQ-EVGGLDPETAYEFRVVSVDGHFNTESATQE 1111
Cdd:cd00063    17 VTLSWtPPEDDGGPITGYVVEYREKGSGDWKEVEVTPGSETSyTLTGLKPGTEYEFRVRAVNGGGESPPSESV 89

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 37.67 E-value: 4.43e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  253 RRQSLALRGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDRITQGHYGkSLVIRQTNFDDAGTYTCDVSNGVGNAQSFSII 332
Cdd:cd05852     9 KKKILAAKGGRVIIECKPKAAPKPKFSWSKGTELLVNNSRISIWDDG-SLEILNITKLDEGSYTCFAENNRGKANSTGVL 87

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 37.47 E-value: 4.45e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617   55 FIIECEADGQPEPEYSWikngkKFDWQAYDNR----MLRQPGRGTLVITIPKDEDRGHYQCFASNEFGT 119
Cdd:cd05743     4 VEFTCVATGVPTPIINW-----RLNWGHVPDSarvsITSEGGYGTLTIRDVKESDQGAYTCEAINTRGM 67

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 37.46 E-value: 4.56e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281360617  255 QSLALRGKRMELFCIYGGTPLPQTVW-SKDGQRIQWSDRITQGHYGkSLVIRQTNFDDAGTYTCDVSNGVGNA 326
Cdd:cd05764     9 ELRVLEGQRATLRCKARGDPEPAIHWiSPEGKLISNSSRTLVYDNG-TLDILITTVKDTGAFTCIASNPAGEA 80

Immunoglobulin V-set domain; This domain is found in antibodies as well as neural protein P0 and CTL4 amongst others.

Pssm-ID: 462230 Cd Length: 109 Bit Score: 38.21 E-value: 4.93e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   438 PAAVSTVDGRNVTIKCRVNGSPK---PLVKWLR-----ASNWL------------TGGRYNVQA-----NGDLEIQDVTF 492
Cdd:pfam07686    3 PREVTVALGGSVTLPCTYSSSMSeasTSVYWYRqppgkGPTFLiayysngseegvKKGRFSGRGdpsngDGSLTIQNLTL 82


                   ....*...
gi 281360617   493 SDAGKYTC 500
Cdd:pfam07686   83 SDSGTYTC 90

First (N-terminal) immunoglobulin (Ig)-like domain of the nectin-like molecules; member of the V-set of Ig superfamily (IgSF) domains; The members here are composed of the N-terminal immunoglobulin (Ig)-like domain of the nectin-like molecules Necl-1 (also known as cell adhesion molecule 3 (CADM3)), Necl-2 (CADM1), Necl-3 (CADM2), and similar proteins. At least five nectin-like molecules have been identified (Necl-1 to Necl-5). They all have an extracellular region containing three Ig-like domains, a transmembrane region, and a cytoplasmic region. The N-terminal Ig-like domain of the extracellular region belongs to the V-type subfamily of Ig domains, is essential to cell-cell adhesion, and plays a part in the interaction with the envelope glycoprotein D of various viruses. Necl-1, Necl-2, and Necl-3 have Ca(2+)-independent homophilic and heterophilic cell-cell adhesion activity. Necl-1 is specifically expressed in neural tissue, and is important to the formation of synapses, axon bundles, and myelinated axons. Necl-2 is expressed in a wide variety of tissues and is a putative tumour suppressor gene which is downregulated in aggressive neuroblastoma. Necl-3 accumulates in central and peripheral nervous system tissue and has been shown to selectively interact with oligodendrocytes. This group also contains Class-I MHC-restricted T-cell-associated molecule (CRTAM), whose expression pattern is consistent with its expression in Class-I MHC-restricted T-cells.

Pssm-ID: 409382 Cd Length: 94 Bit Score: 37.49 E-value: 5.00e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281360617  441 VSTVDGRNVTIKCRVNGSPKPLVKWLRASNW---------LTGGRY---NVQANgDLEIQ--DVTFSDAGKYTC 500
Cdd:cd05717     6 VTVVEGETLTLKCQVSLRDDSSLQWLNPNGQtiyfndkraLRDSRYqllNHSAS-ELSISvsNVTLSDEGVYTC 78

Immunoglobulin (Ig)-like domain of protein zero (P0) and similar proteins; The members here are composed of the immunoglobulin (Ig) domain of protein zero (P0), a myelin membrane adhesion molecule. P0 accounts for over 50% of the total protein in peripheral nervous system (PNS) myelin. P0 is a single-pass transmembrane glycoprotein with a highly basic intracellular domain and an extracellular Ig domain. The extracellular domain of P0 (P0-ED) is similar to the Ig variable domain, carrying one acceptor sequence for N-linked glycosylation. P0 plays a role in membrane adhesion in the spiral wraps of the myelin sheath. The intracellular domain is thought to mediate membrane apposition of the cytoplasmic faces and may, through electrostatic interactions, interact directly with lipid headgroups. It is thought that homophilic interactions of the P0 extracellular domain mediate membrane juxtaposition in the extracellular space of PNS myelin. This group also contains the Ig domain of sodium channel subunit beta-2 (SCN2B), and of epithelial V-like antigen 1 (EVA). EVA, also known as myelin protein zero-like 2, is an adhesion molecule, which may play a role in structural organization of the thymus and early lymphocyte development. SCN2B subunits play a role in determining sodium channel density and function in neurons,and in control of electrical excitability in the brain.

Pssm-ID: 409380 Cd Length: 117 Bit Score: 38.18 E-value: 5.21e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 281360617  261 GKRMELFCIYGGTPLPQTVwSKDGQRIQWSDRITQghYGKSLVIRQTNFDDAGTYTCDVSN 321
Cdd:cd05715    45 NTTESMFHYSKGKPYILKV-GRFKDRVSWAGNPSK--KDASIVISNLQFSDNGTYTCDVKN 102

Fifth immunoglobulin (Ig)-like domain of the carcinoembryonic antigen (CEA) related cell adhesion molecule 5 (CEACAM5) and similar domains; member of the C2-set IgSF domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain of the carcinoembryonic antigen (CEA) related cell adhesion molecule 5 (CEACAM5) and similar domains. The CEA family is a group of anchored or secreted glycoproteins, expressed by epithelial cells, leukocytes, endothelial cells and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), also known as CD66e (Cluster of Differentiation 66e), is a cell surface glycoprotein that plays a role in cell adhesion, intracellular signaling and tumor progression. Diseases associated with CEACAM5 include lung cancer and rectum cancer. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409540 Cd Length: 76 Bit Score: 37.09 E-value: 5.28e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   50 ESDNPFIIECEADGQPEPEYSWIKNGKkfdwqaydNRMLRQpgrgTLVITIPKDEDRGHYQCFASNEFGTATSNSVYVRK 129
Cdd:cd20948     8 LSGENLNLSCHAASNPPAQYSWTINGT--------FQTSSQ----ELFLPAITENNEGTYTCSAHNSLTGKNISLVLSVT 75

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 37.04 E-value: 6.38e-03

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 281360617  249 QYVSRRQSLALR-GKRMELFCIYGGTPLPQTVWSKDGQRIQW--SDRITQGHyGKSLVIRQTNFDDAGTYTCDVSNGVG 324
Cdd:cd04978     1 YWIIEPPSLVLSpGETGELICEAEGNPQPTITWRLNGVPIEPapEDMRRTVD-GRTLIFSNLQPNDTAVYQCNASNVHG 78

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 36.82 E-value: 6.43e-03

                            10        20        30        40        50        60
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 281360617   1041 FRINWLPSTEGHpGTHFFTMHRIKGET---QWIRENEEKNSDYQEVGGLDPETAYEFRVVSVDGH 1102
Cdd:smart00060   17 VTLSWEPPPDDG-ITGYIVGYRVEYREegsEWKEVNVTPSSTSYTLTGLKPGTEYEFRVRAVNGA 80

First immunoglobulin (Ig)-like domain of Tyro3 receptor tyrosine kinase (RTK), and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain of Tyro3 receptor tyrosine kinase (RTK). Tyro3 together with Axl and Mer form the Axl/Tyro3 family of receptor tyrosine kinases (RTKs). This family includes Axl (also known as Ark, Ufo, and Tyro7), Tyro3 (also known as Sky, Rse, Brt, Dtk, and Tif), and Mer (also known as Nyk, c-Eyk, and Tyro12). Axl/Tyro3 family receptors have an extracellular portion with two Ig-like domains followed by two fibronectin-types III (FNIII) domains, a membrane-spanning single helix, and a cytoplasmic tyrosine kinase domain. Axl, Tyro3 and Mer are widely expressed in adult tissues, though they show higher expression in the brain, in the lymphatic and vascular systems, and in the testis. Axl, Tyro3, and Mer bind the vitamin K dependent protein Gas6 with high affinity, and in doing so activate their tyrosine kinase activity. Axl/Gas6 signaling may play a part in cell adhesion processes, prevention of apoptosis, and cell proliferation.

Pssm-ID: 409553 Cd Length: 87 Bit Score: 37.04 E-value: 6.63e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617  260 RGKRMELFCIYGGTPLPQTVWSKDGQRIQWSDR----ITQGHYGKSLVIRQTNFDDAGTYTCDVSNG 322
Cdd:cd20961     7 QGQPVKLNCSVEGMEEPDIQWVKDGAVVQNLDQlyipVSEQHWIGFLSLKSVERSDAGRYWCQVEDG 73

Second immunoglobulin (Ig)-like domain of protein tyrosine kinase (PTK) 7; The members here are composed of the second immunoglobulin (Ig)-like domain in protein tyrosine kinase (PTK) 7, also known as CCK4. PTK7 is a subfamily of the receptor protein tyrosine kinase family, and is referred to as an RPTK-like molecule. RPTKs transduce extracellular signals across the cell membrane and play important roles in regulating cell proliferation, migration, and differentiation. PTK7 is organized as an extracellular portion having seven Ig-like domains, a single transmembrane region, and a cytoplasmic tyrosine kinase-like domain. PTK7 is considered a pseudokinase as it has several unusual residues in some of the highly conserved tyrosine kinase (TK) motifs; it is predicted to lack TK activity. PTK7 may function as a cell-adhesion molecule. PTK7 mRNA is expressed at high levels in placenta, melanocytes, liver, lung, pancreas, and kidney. PTK7 is overexpressed in several cancers, including melanoma and colon cancer lines.

Pssm-ID: 409417 Cd Length: 95 Bit Score: 37.21 E-value: 6.69e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617   29 PRITKQPApgellfkvAQQNKESDNPFIIECEADGQPEPEYSWIKNGKKF-DWQAydNRMLRQPGRgTLVITIPKDEDRG 107
Cdd:cd05760     1 PVVLKHPA--------SAAEIQPSSRVTLRCHIDGHPRPTYQWFRDGTPLsDGQG--NYSVSSKER-TLTLRSAGPDDSG 69

                          90
                  ....*....|....*.
gi 281360617  108 HYQCFASNEFGTATSN 123
Cdd:cd05760    70 LYYCCAHNAFGSVCSS 85

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 37.01 E-value: 6.69e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617  1041 FRINWLPSTEGHpGThfFTMHRIK-----GETQWIRENEEKNSDYQEVGGLDPETAYEFRVVSVDGH 1102
Cdd:pfam00041   16 LTVSWTPPPDGN-GP--ITGYEVEyrpknSGEPWNEITVPGTTTSVTLTGLKPGTEYEVRVQAVNGG 79

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409442 Cd Length: 92 Bit Score: 37.15 E-value: 6.74e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617   57 IECEADGQPEPEYSWIKNGKKFDWQaydnrmlrQPGRG-----TLVITIPKDEDRGHYQCFASNEFG 118
Cdd:cd05856    24 LKCVASGNPRPDITWLKDNKPLTPP--------EIGENkkkkwTLSLKNLKPEDSGKYTCHVSNRAG 82

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 409395 [Multi-domain] Cd Length: 96 Bit Score: 37.12 E-value: 6.96e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 281360617   57 IECEADGQPEPEYSWIK--NGKKFDWQAYDNRML--RQPGRGTLVITIPKDEDRGHYQCFASNEFG 118
Cdd:cd05732    21 LTCEAEGDPIPEITWRRatRGISFEEGDLDGRIVvrGHARVSSLTLKDVQLTDAGRYDCEASNRIG 86

Immunoglobulin (Ig) domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig) domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409398 Cd Length: 101 Bit Score: 37.47 E-value: 7.51e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 281360617  342 TKEPEIATAAEDEEVVFECRAAGVPEPKISWiHNGKPIEQSTPNPRRTVTDN--------TIRIINLVKGDTGNYGCNAT 413
Cdd:cd05735     7 TSYPNTTLATKGQKKEMSCTAHGEKPIIVRW-EKEDTIINPSEMSRYLVTTKevgdevisTLQILPTVREDSGFFSCHAI 85


                  ....
gi 281360617  414 NSLG 417
Cdd:cd05735    86 NSYG 89

Immunoglobulin-like domain of human nephrin and similar proteins; member of the C1-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin-like domain in human nephrin and similar proteins. Nephrin is an integral component of the slit diaphragm and is a central component of the glomerular ultrafilter. Nephrin plays a structural role and has a role in signaling. Nephrin is a transmembrane protein having a short intracellular portion, an extracellular portion comprised of eight Ig-like domains, and one fibronectin type III-like domain. The extracellular portions of nephrin from neighboring foot processes of separate podocyte cells may interact with each other, and in association with other components of the slit diaphragm form a porous molecular sieve within the slit pore. The intracellular portion of nephrin is associated with linker proteins, which connect nephrin to the actin cytoskeleton. The intracellular portion is tyrosine phosphorylated, and mediates signaling from the slit diaphragm into the podocytes.

Pssm-ID: 143250 Cd Length: 109 Bit Score: 37.60 E-value: 7.86e-03

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 281360617  360 CRAAGVPEPKISWIHNGKPIEQStpNPRRT--------VTDNTIRIINLVKG-DTGNYGCNATNSLG 417
Cdd:cd05773    30 CQAQGVPRVQFRWAKNGVPLDLG--NPRYEettehtgtVHTSILTIINVSAAlDYALFTCTAHNSLG 94

Immunoglobulin (Ig)-like domain of titin and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain found in titin-like proteins and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is a giant protein; depending on isoform composition, it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone. It appears to function similarly to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. Within the sarcomere, titin is also attached to or is associated with myosin binding protein C (MyBP-C). MyBP-C appears to contribute to the generation of passive tension by titin and like titin has repeated Ig-like and FN-III domains. Also included in this group are worm twitchin and insect projectin, thick filament proteins of invertebrate muscle which also have repeated Ig-like and FN-III domains.

Pssm-ID: 409406 [Multi-domain] Cd Length: 82 Bit Score: 36.80 E-value: 8.02e-03

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 281360617  364 GVPEPKISWIHNGKPIEQSTpnpRRTVT---DNTIRII-NLVKGDTGNYGCNATNSLG 417
Cdd:cd05748    18 GRPTPTVTWSKDGQPLKETG---RVQIEttaSSTSLVIkNAKRSDSGKYTLTLKNSAG 72