Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 241 KPVITMEPLGLAeegfwASEREEVTLSCLAASNPPSHYVWLRDHTQVHTGP-----------TYIIARAGRVHTGLYTCL 309
Cdd:pfam13927   1 KPVITVSPSSVT-----VREGETVTLTCEATGSPPPTITWYKNGEPISSGStrsrslsgsnsTLTISNVTRSDAGTYTCV 75

                  ...
gi 1622867749 310 AHN 312
Cdd:pfam13927  76 ASN 78

Fibronectin type III domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 598 PAPPNVTISRLTygrhRREVQLQWAIA--GPGNLTGFLVQRKaSALGPGAGAWETaasdIEPESRGRRLGGLDPGVLYAF 675
Cdd:pfam00041   1 SAPSNLTVTDVT----STSLTVSWTPPpdGNGPITGYEVEYR-PKNSGEPWNEIT----VPGTTTSVTLTGLKPGTEYEV 71

                          90
                  ....*....|....
gi 1622867749 676 RILALNHHTAGHPS 689
Cdd:pfam00041  72 RVQAVNGGGEGPPS 85

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 241 KPVITMEPLGLAeegfwASEREEVTLSCLAASNPPSHYVWLRDHTQVHTGP-----------TYIIARAGRVHTGLYTCL 309
Cdd:pfam13927   1 KPVITVSPSSVT-----VREGETVTLTCEATGSPPPTITWYKNGEPISSGStrsrslsgsnsTLTISNVTRSDAGTYTCV 75

                  ...
gi 1622867749 310 AHN 312
Cdd:pfam13927  76 ASN 78

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

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749  257 WASEREEVTLSCLAASNPPSHYVWLRDHTQVHTGP------------TYIIARAGRVHTGLYTCLAHNSYLDSRTQTTVQ 324
Cdd:smart00410   5 TVKEGESVTLSCEASGSPPPEVTWYKQGGKLLAESgrfsvsrsgstsTLTISNVTPEDSGTYTCAATNSSGSASSGTTLT 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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 264 VTLSCLAASNPPSHYVWLRDHTQVHTGPTY-----------IIARAGRVHTGLYTCLAHNSYLDSRTQTT 322
Cdd:cd00096     1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDsrrselgngtlTISNVTLEDSGTYTCVASNSAGGSASASV 70

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 500 APQLDVAEPRVSVLEGGEAWLECSLRGgTPPAQLLWLgPQQQQVDHGTSGFMLHPEGAQLRlgIYNADPAHHrGTYQCVA 579
Cdd:cd20976     1 APSFSSVPKDLEAVEGQDFVAQCSARG-KPVPRITWI-RNAQPLQYAADRSTCEAGVGELH--IQDVLPEDH-GTYTCLA 75

                          90
                  ....*....|....*
gi 1622867749 580 RNAVGNSSRSVLLEV 594
Cdd:cd20976    76 KNAAGQVSCSAWVTV 90

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1622867749 149 KPQVRLSNPSPV--EGASVVATCAVREGTEPvTFAWQHQ----ASQGLGEALVGVTEPLFRLDPVNRTHLGWYMCSARN 221
Cdd:pfam13927   1 KPVITVSPSSVTvrEGETVTLTCEATGSPPP-TITWYKNgepiSSGSTRSRSLSGSNSTLTISNVTRSDAGTYTCVASN 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.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749  598 PAPPNVTISRLTygrhRREVQLQWAIAGPGNLTGFLVQRKASaLGPGAGAWETAASDiePESRGRRLGGLDPGVLYAFRI 677
Cdd:smart00060   2 SPPSNLRVTDVT----STSVTLSWEPPPDDGITGYIVGYRVE-YREEGSEWKEVNVT--PSSTSYTLTGLKPGTEYEFRV 74

                   ....*....
gi 1622867749  678 LALNHHTAG 686
Cdd:smart00060  75 RAVNGAGEG 83

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 241 KPVITMEPLGLAeegfwASEREEVTLSCLAASNPPSHYVWLRDHTQVHTGP-----------TYIIARAGRVHTGLYTCL 309
Cdd:pfam13927   1 KPVITVSPSSVT-----VREGETVTLTCEATGSPPPTITWYKNGEPISSGStrsrslsgsnsTLTISNVTRSDAGTYTCV 75

                  ...
gi 1622867749 310 AHN 312
Cdd:pfam13927  76 ASN 78

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

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749  257 WASEREEVTLSCLAASNPPSHYVWLRDHTQVHTGP------------TYIIARAGRVHTGLYTCLAHNSYLDSRTQTTVQ 324
Cdd:smart00410   5 TVKEGESVTLSCEASGSPPPEVTWYKQGGKLLAESgrfsvsrsgstsTLTISNVTPEDSGTYTCAATNSSGSASSGTTLT 84

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 501 PQLDVAEPRVSVLEGGEAWLECSLRGGtPPAQLLWLGPQQQQVDHGTSGFMLHPEGAQLRlgIYNADPaHHRGTYQCVAR 580
Cdd:pfam13927   2 PVITVSPSSVTVREGETVTLTCEATGS-PPPTITWYKNGEPISSGSTRSRSLSGSNSTLT--ISNVTR-SDAGTYTCVAS 77

                  .
gi 1622867749 581 N 581
Cdd:pfam13927  78 N 78

Fibronectin type III domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 598 PAPPNVTISRLTygrhRREVQLQWAIA--GPGNLTGFLVQRKaSALGPGAGAWETaasdIEPESRGRRLGGLDPGVLYAF 675
Cdd:pfam00041   1 SAPSNLTVTDVT----STSLTVSWTPPpdGNGPITGYEVEYR-PKNSGEPWNEIT----VPGTTTSVTLTGLKPGTEYEV 71

                          90
                  ....*....|....
gi 1622867749 676 RILALNHHTAGHPS 689
Cdd:pfam00041  72 RVQAVNGGGEGPPS 85

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 500 APQLDVAEPRVSVLEGGEAWLECSLRGgTPPAQLLWLgPQQQQVDHGTSGFMLHPEGAQLRlgIYNADPAHHrGTYQCVA 579
Cdd:cd20976     1 APSFSSVPKDLEAVEGQDFVAQCSARG-KPVPRITWI-RNAQPLQYAADRSTCEAGVGELH--IQDVLPEDH-GTYTCLA 75

                          90
                  ....*....|....*
gi 1622867749 580 RNAVGNSSRSVLLEV 594
Cdd:cd20976    76 KNAAGQVSCSAWVTV 90

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 505 VAEPRVSVLEGGEAWLECSLRGGTPPAQLLWL-----GPQQQQVDHGTSGfmlhpeGAQLRLGIYNADPAHHrGTYQCVA 579
Cdd:pfam00047   1 SAPPTVTVLEGDSATLTCSASTGSPGPDVTWSkeggtLIESLKVKHDNGR------TTQSSLLISNVTKEDA-GTYTCVV 73

                          90
                  ....*....|.
gi 1622867749 580 RNAVGNSSRSV 590
Cdd:pfam00047  74 NNPGGSATLST 84

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 515 GGEAWLECSLRGGTPPAQLLW-LGPQQQQVDHGTSGFMLHPEGAQLrlgIYNADPAHHRGTYQCVARNAVGNSSRSVLLE 593
Cdd:cd20959    17 GMRAQLHCGVPGGDLPLNIRWtLDGQPISDDLGITVSRLGRRSSIL---SIDSLEASHAGNYTCHARNSAGSASYTAPLT 93

                  .
gi 1622867749 594 V 594
Cdd:cd20959    94 V 94

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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1622867749 259 SEREEVTLSCLAASNPPSHYVWLRDHTQVHTGPTY---------IIARAGRVH-TGLYTCLAHNSY 314
Cdd:cd04967    17 SDEKKVALNCRARANPVPSYRWLMNGTEIDLESDYryslvdgtlVISNPSKAKdAGHYQCLATNTV 82

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 510 VSVLEGGEAWLECSLRGGTPPAqLLWLGPQQQQVDHGTSGFMLHPEGAQLRlgiYNADPAHHRGTYQCVARNAVGNSSRS 589
Cdd:cd20969    12 VFVDEGHTVQFVCRADGDPPPA-ILWLSPRKHLVSAKSNGRLTVFPDGTLE---VRYAQVQDNGTYLCIAANAGGNDSMP 87

                  ....*
gi 1622867749 590 VLLEV 594
Cdd:cd20969    88 AHLHV 92

Fibronectin type 3 domain [General function prediction only];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 574 TYQCVARNAVGNSSRSVLLEVLRYPAPP----NVTISRLTYGRhrreVQLQWAIAGPGNLTGFLVQRKASalgpGAGAWE 649
Cdd:COG3401   206 YYRVAATDTGGESAPSNEVSVTTPTTPPsaptGLTATADTPGS----VTLSWDPVTESDATGYRVYRSNS----GDGPFT 277

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 650 TAASDIEPE---SrgrrlgGLDPGVLYAFRILALNhhTAGHPS----EVKIPADPPFSAYPAVLGAAGTG 712
Cdd:COG3401   278 KVATVTTTSytdT------GLTNGTTYYYRVTAVD--AAGNESapsnVVSVTTDLTPPAAPSGLTATAVG 339

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.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749  598 PAPPNVTISRLTygrhRREVQLQWAIAGPGNLTGFLVQRKASaLGPGAGAWETAASDiePESRGRRLGGLDPGVLYAFRI 677
Cdd:smart00060   2 SPPSNLRVTDVT----STSVTLSWEPPPDDGITGYIVGYRVE-YREEGSEWKEVNVT--PSSTSYTLTGLKPGTEYEFRV 74

                   ....*....
gi 1622867749  678 LALNHHTAG 686
Cdd:smart00060  75 RAVNGAGEG 83

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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1622867749 258 ASEREEVTLSCLAASNPPSHYVWLRDHTQVHT----------GPTYIIARAGRVHTGLYTCLAHN 312
Cdd:cd20970    14 AREGENATFMCRAEGSPEPEISWTRNGNLIIEfntryivrenGTTLTIRNIRRSDMGIYLCIASN 78

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 505 VAEPRVSVLEGGEAWLECSLRGGTPPAQLLWLGPQQQQvdHGTSGFMLHPEGAqlrLGIYNADPAhHRGTYQCVARNAV- 583
Cdd:cd04979     1 TSFKQISVKEGDTVILSCSVKSNNAPVTWIHNGKKVPR--YRSPRLVLKTERG---LLIRSAQEA-DAGVYECHSGERVl 74

                          90
                  ....*....|..
gi 1622867749 584 GNSSRSVLLEVL 595
Cdd:cd04979    75 GSTLRSVTLHVL 86

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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1622867749 161 EGASVVATCAVREGTEPVTFAWQHQASQGLGEALVGVTEPL-----FRLDPVNRTHLGWYMCSARNS 222
Cdd:pfam00047  10 EGDSATLTCSASTGSPGPDVTWSKEGGTLIESLKVKHDNGRttqssLLISNVTKEDAGTYTCVVNNP 76

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 508 PRVSVLEGGEAWLECSLRGGTPPAqLLWLGPQQQQVdHGTSGFMLHPEGAqLRLGIYNADPAhhrGTYQCVARNAVGNSS 587
Cdd:cd05764     8 HELRVLEGQRATLRCKARGDPEPA-IHWISPEGKLI-SNSSRTLVYDNGT-LDILITTVKDT---GAFTCIASNPAGEAT 81

                  ....*..
gi 1622867749 588 RSVLLEV 594
Cdd:cd05764    82 ARVELHI 88

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).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 252 AEEGFWASEREEVTLSCLAASNPPSHYVWLRDHTQVHTGPTYIIARAGRV-------------HTGLYTCLAHNSYLDSR 318
Cdd:cd20977     6 VSKDMMAKAGDVTMIYCMYGSNPTAHPNYFKNGKDVNGNPEDRITRHNRTsgkrllfkttlpeDEGVYTCEVDNGVGKPQ 85

                  ....*....
gi 1622867749 319 TQTTvQLTI 327
Cdd:cd20977    86 KHSL-KLTV 93

First immunoglobulin (Ig)-like domain of neural cell adhesion molecule NCAM-1, 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 of neural cell adhesion molecule NCAM-1. NCAM-1 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-nonNCAM) 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 the Ig1, Ig2, and Ig3 domains. 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). 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 502 QLDVAEPRVSVLEGGEAWLECSLRGgtPPAQLLWLGPQQQQVDHGTSGFMLHPEGAQL-RLGIYNADpAHHRGTYQCVAR 580
Cdd:cd04977     2 QVKIIPSYAEISVGESKFFLCKVSG--DAKNINWVSPNGEKVLTKHGNLKVVNHGSVLsSLTIYNAN-INDAGIYKCVAT 78

                          90
                  ....*....|....*.
gi 1622867749 581 NAVGNSSR-SVLLEVL 595
Cdd:cd04977    79 NGKGTESEaTVKLDII 94

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622867749 511 SVLEGGEAWLECSLRGGTPPAQLLW-----LGPQQQQVDHG--TSGFMLHPEGAQLrlgIYNADPAHHRGTYQCVARNAV 583
Cdd:cd20950     8 SATIGNRAVLTCSEPDGSPPSEYTWfkdgvVMPTNPKSTRAfsNSSYSLDPTTGEL---VFDPLSASDTGEYSCEARNGY 84

                          90
                  ....*....|...
gi 1622867749 584 GNS--SRSVLLEV 594
Cdd:cd20950    85 GTPmrSNAVRMEA 97