First immunoglobulin (Ig)-like domain of carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM); The members here are composed of the immunoglobulin (Ig)-like domain 1 in carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) proteins. 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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005  36 LTIETVPPLAAEGSDVLLLAHNVTKNPLGYAWYRGERVDNSQLIASYRVAT---TKGPAHSGRETLYPNGTLLIQNVTQK 112
Cdd:cd05774   1 LTIELVPPQVAEGENVLLLVHNLPENLLAYAWYKGKTVSPNFLIASYIISTnssTPGPAYSGRETIYPNGSLLIQNVTQK 80

                        90       100
                ....*....|....*....|....*
gi 45430005 113 DTGSYTLLVTKDDLQTERQTGHLHI 137
Cdd:cd05774  81 DTGFYTLQTITADLQTEQASVHLQV 105

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        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005 236 QPSLQASNTTVIEHEGPVVLTCLTDETGISIRWFFKGRSLLLAQRMTLSSDNSTLTIDPVSRQDAGDYQCEVSNRGNSSR 315
Cdd:cd05740   1 KPFISSNNSNPVEDKDAVTLTCEPETQNTSYLWWFNGQSLPVTPRLTLSNGNRTLTLLNVTREDAGAYQCEISNPVSANR 80

                ....*...
gi 45430005 316 SDPLSLHV 323
Cdd:cd05740  81 SDPVTLDV 88

First immunoglobulin (Ig)-like domain of carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM); The members here are composed of the immunoglobulin (Ig)-like domain 1 in carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) proteins. 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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005  36 LTIETVPPLAAEGSDVLLLAHNVTKNPLGYAWYRGERVDNSQLIASYRVAT---TKGPAHSGRETLYPNGTLLIQNVTQK 112
Cdd:cd05774   1 LTIELVPPQVAEGENVLLLVHNLPENLLAYAWYKGKTVSPNFLIASYIISTnssTPGPAYSGRETIYPNGSLLIQNVTQK 80

                        90       100
                ....*....|....*....|....*
gi 45430005 113 DTGSYTLLVTKDDLQTERQTGHLHI 137
Cdd:cd05774  81 DTGFYTLQTITADLQTEQASVHLQV 105

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005 236 QPSLQASNTTVIEHEGPVVLTCLTDETGISIRWFFKGRSLLLAQRMTLSSDNSTLTIDPVSRQDAGDYQCEVSNRGNSSR 315
Cdd:cd05740   1 KPFISSNNSNPVEDKDAVTLTCEPETQNTSYLWWFNGQSLPVTPRLTLSNGNRTLTLLNVTREDAGAYQCEISNPVSANR 80

                ....*...
gi 45430005 316 SDPLSLHV 323
Cdd:cd05740  81 SDPVTLDV 88

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

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 45430005    158 DTVVLTCGPETQNTSYMWWINN--QSLPNGTRLELSEDKR--TLTVFNVTRNDTGPYVCEAWNPvSVSRSDPFTLNV 230
Cdd:smart00410  10 ESVTLSCEASGSPPPEVTWYKQggKLLAESGRFSVSRSGStsTLTISNVTPEDSGTYTCAATNS-SGSASSGTTLTV 85

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

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005    242 SNTTVIEHEgPVVLTC-LTDETGISIRWFFKGRSLLLAQ-RMTLSSD--NSTLTIDPVSRQDAGDYQCEVSNRGNSSRSd 317
Cdd:smart00410   2 PSVTVKEGE-SVTLSCeASGSPPPEVTWYKQGGKLLAESgRFSVSRSgsTSTLTISNVTPEDSGTYTCAATNSSGSASS- 79

                   ....*.
gi 45430005    318 PLSLHV 323
Cdd:smart00410  80 GTTLTV 85

IL-1 receptor-like protein; Provisional

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 45430005  169 QNTSYMWWINNQSLPNGTRLELSEDKRTLTVFNVTRNDTGPYVC 212
Cdd:PHA02826 162 KDYTLTWYKNGNIVLYTDRIQLRNNNSTLVIKSATHDDSGIYTC 205

First immunoglobulin (Ig)-like domain of carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM); The members here are composed of the immunoglobulin (Ig)-like domain 1 in carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) proteins. 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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005  36 LTIETVPPLAAEGSDVLLLAHNVTKNPLGYAWYRGERVDNSQLIASYRVAT---TKGPAHSGRETLYPNGTLLIQNVTQK 112
Cdd:cd05774   1 LTIELVPPQVAEGENVLLLVHNLPENLLAYAWYKGKTVSPNFLIASYIISTnssTPGPAYSGRETIYPNGSLLIQNVTQK 80

                        90       100
                ....*....|....*....|....*
gi 45430005 113 DTGSYTLLVTKDDLQTERQTGHLHI 137
Cdd:cd05774  81 DTGFYTLQTITADLQTEQASVHLQV 105

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005 236 QPSLQASNTTVIEHEGPVVLTCLTDETGISIRWFFKGRSLLLAQRMTLSSDNSTLTIDPVSRQDAGDYQCEVSNRGNSSR 315
Cdd:cd05740   1 KPFISSNNSNPVEDKDAVTLTCEPETQNTSYLWWFNGQSLPVTPRLTLSNGNRTLTLLNVTREDAGAYQCEISNPVSANR 80

                ....*...
gi 45430005 316 SDPLSLHV 323
Cdd:cd05740  81 SDPVTLDV 88

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 45430005   237 PSLQASNTTVIEHEG-PVVLTCLTD-ETGISIRWFFKGRSLL--LAQRMTLSSDNSTLTIDPVSRQDAGDYQCEVSN 309
Cdd:pfam13927   2 PVITVSPSSVTVREGeTVTLTCEATgSPPPTITWYKNGEPISsgSTRSRSLSGSNSTLTISNVTRSDAGTYTCVASN 78

Immunoglobulin V-set domain; This domain is found in antibodies as well as neural protein P0 and CTL4 amongst others.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005    42 PPLAAEGSDVLLLAH---NVTKNPLGYAWYRGER-VDNSQLIASY---RVATTKGPAHSGRETL-YPNGTLLIQNVTQKD 113
Cdd:pfam07686   5 EVTVALGGSVTLPCTyssSMSEASTSVYWYRQPPgKGPTFLIAYYsngSEEGVKKGRFSGRGDPsNGDGSLTIQNLTLSD 84

                          90       100
                  ....*....|....*....|....*
gi 45430005   114 TGSYTLLVTKDDLQTERQTGHLHIL 138
Cdd:pfam07686  85 SGTYTCAVIPSGEGVFGKGTRLTVL 109

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 45430005 253 VVLTC-LTDETGISIRWFFKGRSLLLAQ--RMTLSSDNSTLTIDPVSRQDAGDYQCEVSNRGNSSRS 316
Cdd:cd00096   1 VTLTCsASGNPPPTITWYKNGKPLPPSSrdSRRSELGNGTLTISNVTLEDSGTYTCVASNSAGGSAS 67

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 45430005   242 SNTTVIEHEgPVVLTCL--TDETGISIRWFFKGRSLLLAQRMTLSSD---NSTLTIDPVSRQDAGDYQCEVSNRGNSS 314
Cdd:pfam00047   4 PTVTVLEGD-SATLTCSasTGSPGPDVTWSKEGGTLIESLKVKHDNGrttQSSLLISNVTKEDAGTYTCVVNNPGGSA 80

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005 243 NTTVIEHEgPVVLTCLTDETGI-SIRWFFKGRSLLLAQRMTLSSdNSTLTIDPVSR-QDAGDYQCEVSNR-GNSSRSdpl 319
Cdd:cd20958   9 NLTAVAGQ-TLRLHCPVAGYPIsSITWEKDGRRLPLNHRQRVFP-NGTLVIENVQRsSDEGEYTCTARNQqGQSASR--- 83

                ....*
gi 45430005 320 SLHVK 324
Cdd:cd20958  84 SVFVK 88

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 45430005   158 DTVVLTCGPETQ--NTSYMWWINNQSLPNGTRLELSEDKRT---LTVFNVTRNDTGPYVCEAWNPVSVS 221
Cdd:pfam00047  12 DSATLTCSASTGspGPDVTWSKEGGTLIESLKVKHDNGRTTqssLLISNVTKEDAGTYTCVVNNPGGSA 80

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005   143 RPVITSNNSNPWEhQDTVVLTC-GPETQNTSYMWWINNQSLPNGTRLelsedkrtlTVFNVTRNDTGPYVCEAWNPVSVS 221
Cdd:pfam13895   1 KPVLTPSPTVVTE-GEPVTLTCsAPGNPPPSYTWYKDGSAISSSPNF---------FTLSVSAEDSGTYTCVARNGRGGK 70

                  ....*....
gi 45430005   222 RSDPFTLNV 230
Cdd:pfam13895  71 VSNPVELTV 79

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 45430005  95 RETLYPNGTLLIQNVTQK-DTGSYTLLVTKDDLQTERQTGHLHI 137
Cdd:cd20958  46 RQRVFPNGTLVIENVQRSsDEGEYTCTARNQQGQSASRSVFVKV 89

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 45430005 251 GPVVLTCLTDETGI-SIRWFFKGRSLLLAQRMTLSSDNsTLTIDPVSRQDAGDYQCEVSNRGNSSRS 316
Cdd:cd20957  17 RTAVFNCSVTGNPIhTVLWMKDGKPLGHSSRVQILSED-VLVIPSVKREDKGMYQCFVRNDGDSAQA 82

First Ig-like domain of Junctional adhesion molecule-1 (JAM1)and similar domains; a member of the V-set of IgSF domains; The members here are composed of the first Ig-like domain of Junctional Adhesion Molecule-1 (JAM1)and similar domains. 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 first Ig-like domain of JAM1 is a member of the V-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C'-C" in the other.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005 238 SLQASNTTVIEHE-GPVVLTCLTDETGISIR--WFFKGR--SLLLAQRMTLSSD--------NSTLTIDPVSRQDAGDYQ 304
Cdd:cd20946   1 TVPSSQQVVTVVEnQEVILSCKTPKKTSSPRveWKKLQRdvTFVVFQNNKIQGDykgraeilGTNITIKNVTRSDSGKYR 80

                ....*..
gi 45430005 305 CEVSNRG 311
Cdd:cd20946  81 CEVSARS 87

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005   236 QPSLQASNTTVieHEG-PVVLTCLTDET-GISIRWFfKGRSLLlaqrmtlsSDNSTLTIDPVSRQDAGDYQCEVSNRGNS 313
Cdd:pfam13895   1 KPVLTPSPTVV--TEGePVTLTCSAPGNpPPSYTWY-KDGSAI--------SSSPNFFTLSVSAEDSGTYTCVARNGRGG 69

                          90
                  ....*....|
gi 45430005   314 SRSDPLSLHV 323
Cdd:pfam13895  70 KVSNPVELTV 79

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005 243 NTTVIEhEGPVVLTCLT-DETGISIRWFfKGRSLLLAQRMTLSSDNSTLTIDPVSRQDAGDYQCEVSNRGNSSRSDPLSL 321
Cdd:cd20968   8 NVTIIE-GLKAVLPCTTmGNPKPSVSWI-KGDDLIKENNRIAVLESGSLRIHNVQKEDAGQYRCVAKNSLGIAYSKPVTI 85

                ...
gi 45430005 322 HVK 324
Cdd:cd20968  86 EVE 88

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*...
gi 45430005 160 VVLTCGPETQ-NTSYMWWINNQSLPNGTRLELSEDKrTLTVFNVTRNDTGPYVCEAWN 216
Cdd:cd05852  20 VIIECKPKAApKPKFSWSKGTELLVNNSRISIWDDG-SLEILNITKLDEGSYTCFAEN 76

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor (VEGF) receptor(R); member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor (VEGF) receptor(R). 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 (also known as Flt-1), VEGFR-2 (also known as KDR or Flk-1) and VEGFR-3 (also known as Flt-4). VEGF_A interacts with both VEGFR-1 and VEGFR-2. VEGFR-1 binds strongest to VEGF, VEGF-2 binds more weakly. VEGFR-3 appears not to bind VEGF, but binds other members of the VEGF family (VEGF-C and -D). VEGFRs bind VEGFs with high affinity with 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-2 and -1 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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005 254 VLTC--LTD-ETGISIRWFFKG-----RSLLLAQRMTLSSD----NSTLTIDPVSRQDAGDYQCEVSNrGNSSRSDPLSL 321
Cdd:cd05862  20 VLNCtaRTElNVGVDFQWDYPGkkeqrRASVRRRRKQQSSEatefSSTLTIDNVTLSDKGLYTCAASS-GPMFKKNSTSV 98

                ..
gi 45430005 322 HV 323
Cdd:cd05862  99 IV 100

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005 235 AQPSLQASNTTVIEhegpvvLTCLTDETGISIRWFFKGRSLLLAQRMTLSSDNS--TLTIDPVSRQDAGDYQCEVsnrGN 312
Cdd:cd20967   3 AQPAVQVSKGHKIR------LTVELADPDAEVKWYKDGQELQSSSKVIFESIGAkrTLTVQQASLADAGEYQCVA---GG 73

                ....*....
gi 45430005 313 SSRSDPLSL 321
Cdd:cd20967  74 EKCSFELFV 82

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*...
gi 45430005 160 VVLTCGPE-TQNTSYMWWINNQSLPNGTRLELSEDkRTLTVFNVTRNDTGPYVCEAWN 216
Cdd:cd04969  20 VIIECKPKaSPKPTISWSKGTELLTNSSRICILPD-GSLKIKNVTKSDEGKYTCFAVN 76

IL-1 receptor-like protein; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005  189 ELSEDKRTLTVFNVTRNDTGPYVCEAwnpVSVSRSDPFTLNVlypvaqpSLQASNTTVIEHEG-PVVLTCLtDETGIS-- 265
Cdd:PHA02826  92 EIGDRSENLWIGNVINIDEGIYICTI---SSGNICEESTIRL-------TFDSGTINYQFNSGkDSKLHCY-GTDGISst 160

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*
gi 45430005  266 -----IRWFFKGRSLLLAQRMTLSSDNSTLTIDPVSRQDAGDYQC 305
Cdd:PHA02826 161 fkdytLTWYKNGNIVLYTDRIQLRNNNSTLVIKSATHDDSGIYTC 205

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 45430005 245 TVIEHEGPVVLTC---LTDETGiSIRWFFKGrSLLlaqrmtlSSDNSTLTIDPVSRQDAGDYQCEvsnRGNSSRSDPLSL 321
Cdd:cd05752  10 TTVFQGEKVTLTCqgfYSPEQN-STQWYHNG-TLI-------SSTSSSYRIVAATVNDSGEYRCQ---TQGSSLSDPVHL 77

                ..
gi 45430005 322 HV 323
Cdd:cd05752  78 EV 79

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 45430005 158 DTVVLTCGPETQNTSYMWWIN-NQSLPNGtRLELSEDKRTLTVFNVTRNDTGPYVCEAWNPVSVSRSDpFTLNV 230
Cdd:cd05731  11 GVLLLECIAEGLPTPDIRWIKlGGELPKG-RTKFENFNKTLKIENVSEADSGEYQCTASNTMGSARHT-ISVTV 82