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 665401767  180 ENSTVVTTQIGATAHVPCTV---HHIGEGVVSWIRKKDYHLLTVGLTTYSSD-------ERFSATHLKHSEDWTLQIKFV 249
Cdd:pfam07686   1 QTPREVTVALGGSVTLPCTYsssMSEASTSVYWYRQPPGKGPTFLIAYYSNGseegvkkGRFSGRGDPSNGDGSLTIQNL 80

                          90       100
                  ....*....|....*....|....*....
gi 665401767  250 QLRDAGVYECQVSTHPPTSIF--LHLSVV 276
Cdd:pfam07686  81 TLSDSGTYTCAVIPSGEGVFGkgTRLTVL 109

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 665401767  180 ENSTVVTTQIGATAHVPCTV---HHIGEGVVSWIRKKDYHLLTVGLTTYSSD-------ERFSATHLKHSEDWTLQIKFV 249
Cdd:pfam07686   1 QTPREVTVALGGSVTLPCTYsssMSEASTSVYWYRQPPGKGPTFLIAYYSNGseegvkkGRFSGRGDPSNGDGSLTIQNL 80

                          90       100
                  ....*....|....*....|....*....
gi 665401767  250 QLRDAGVYECQVSTHPPTSIF--LHLSVV 276
Cdd:pfam07686  81 TLSDSGTYTCAVIPSGEGVFGkgTRLTVL 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 665401767 295 LRLQCRVVQNTEASeyIFWYHDNRminyDIDRGINVSTEPDFQSSELTIQRTRREHSGNFTCVASN 360
Cdd:cd00096    1 VTLTCSASGNPPPT--ITWYKNGK----PLPPSSRDSRRSELGNGTLTISNVTLEDSGTYTCVASN 60

Immunoglobulin variable domain (IgV); The members here are composed of the immunoglobulin variable domain (IgV). The IgV family contains the standard Ig superfamily V-set AGFCC'C"/DEB domain topology, and are components of immunoglobulin (Ig) and T cell receptors. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. In Ig, each chain is composed of one variable domain (IgV) and one or more constant domains (IgC); these names reflect the fact that the variability in sequences is higher in the variable domain than in the constant domain. Within the variable domain, there are regions of even more variability called the hypervariable or complementarity-determining regions (CDRs) which are responsible for antigen binding. A predominant feature of most Ig domains is the disulfide bridge connecting 2 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" strands in the other.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 665401767 179 TENSTVVTTQIGATAHVPCTVHH-IGEGVVSWIRKKD--------YHLLTVGLTTYSSDERFSATHLKhSEDWTLQIKFV 249
Cdd:cd00099    2 TQSPRSLSVQEGESVTLSCEVSSsFSSTYIYWYRQKPgqgpefliYLSSSKGKTKGGVPGRFSGSRDG-TSSFSLTISNL 80

                         90
                 ....*....|....*...
gi 665401767 250 QLRDAGVYECQVSTHPPT 267
Cdd:cd00099   81 QPEDSGTYYCAVSESGGT 98

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 665401767  180 ENSTVVTTQIGATAHVPCTV---HHIGEGVVSWIRKKDYHLLTVGLTTYSSD-------ERFSATHLKHSEDWTLQIKFV 249
Cdd:pfam07686   1 QTPREVTVALGGSVTLPCTYsssMSEASTSVYWYRQPPGKGPTFLIAYYSNGseegvkkGRFSGRGDPSNGDGSLTIQNL 80

                          90       100
                  ....*....|....*....|....*....
gi 665401767  250 QLRDAGVYECQVSTHPPTSIF--LHLSVV 276
Cdd:pfam07686  81 TLSDSGTYTCAVIPSGEGVFGkgTRLTVL 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 665401767 295 LRLQCRVVQNTEASeyIFWYHDNRminyDIDRGINVSTEPDFQSSELTIQRTRREHSGNFTCVASN 360
Cdd:cd00096    1 VTLTCSASGNPPPT--ITWYKNGK----PLPPSSRDSRRSELGNGTLTISNVTLEDSGTYTCVASN 60

Immunoglobulin variable domain (IgV); The members here are composed of the immunoglobulin variable domain (IgV). The IgV family contains the standard Ig superfamily V-set AGFCC'C"/DEB domain topology, and are components of immunoglobulin (Ig) and T cell receptors. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. In Ig, each chain is composed of one variable domain (IgV) and one or more constant domains (IgC); these names reflect the fact that the variability in sequences is higher in the variable domain than in the constant domain. Within the variable domain, there are regions of even more variability called the hypervariable or complementarity-determining regions (CDRs) which are responsible for antigen binding. A predominant feature of most Ig domains is the disulfide bridge connecting 2 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" strands in the other.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 665401767 179 TENSTVVTTQIGATAHVPCTVHH-IGEGVVSWIRKKD--------YHLLTVGLTTYSSDERFSATHLKhSEDWTLQIKFV 249
Cdd:cd00099    2 TQSPRSLSVQEGESVTLSCEVSSsFSSTYIYWYRQKPgqgpefliYLSSSKGKTKGGVPGRFSGSRDG-TSSFSLTISNL 80

                         90
                 ....*....|....*...
gi 665401767 250 QLRDAGVYECQVSTHPPT 267
Cdd:cd00099   81 QPEDSGTYYCAVSESGGT 98

Immunoglobulin I-set domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 665401767  280 EITGPPIRY-LTPGSTLRLQCRVVQNTEASeyIFWYHDNRMINydIDRGINVSTEPDfqSSELTIQRTRREHSGNFTCVA 358
Cdd:pfam07679   2 KFTQKPKDVeVQEGESARFTCTVTGTPDPE--VSWFKDGQPLR--SSDRFKVTYEGG--TYTLTISNVQPDDSGKYTCVA 75

                  ..
gi 665401767  359 SN 360
Cdd:pfam07679  76 TN 77

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 665401767 292 GSTLRLQCrVVQNTEASEYIfWYHDNRMINYDIDRginVSTEPdfQSSELTIQRTRREHSGNFTCVASN 360
Cdd:cd20976   16 GQDFVAQC-SARGKPVPRIT-WIRNAQPLQYAADR---STCEA--GVGELHIQDVLPEDHGTYTCLAKN 77

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 665401767  280 EITGPPIRYlTPGSTLRLQCRVVQNTEASeyIFWYHDNRMINydidrginvstepdfQSSELTIQRTRREHSGNFTCVAS 359
Cdd:pfam13895   3 VLTPSPTVV-TEGEPVTLTCSAPGNPPPS--YTWYKDGSAIS---------------SSPNFFTLSVSAEDSGTYTCVAR 64

                  ...
gi 665401767  360 NTQ 362
Cdd:pfam13895  65 NGR 67

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 665401767  179 TENSTVVTTQIGATAHVPCTVHHIGEGVVSWIRKkdyhlltvGLTTYSSDERFSATHLKHSedwTLQIKFVQLRDAGVYE 258
Cdd:pfam13927   5 TVSPSSVTVREGETVTLTCEATGSPPPTITWYKN--------GEPISSGSTRSRSLSGSNS---TLTISNVTRSDAGTYT 73

                  ....
gi 665401767  259 CQVS 262
Cdd:pfam13927  74 CVAS 77

Immunoglobulin variable domain (IgV) in Cluster of Differentiation (CD) 86; The members here are composed of the immunoglobulin variable region (IgV) in the Cluster of Differentiation (CD) 86). Glycoproteins B7-1 (also known as cluster of differentiation (CD) 80) and B7-2 (also known as CD86) are expressed on antigen-presenting cells and deliver the co-stimulatory signal through CD28 and CTLA-4 (also known as CD152) on T cells. signaling through CD28 augments the T-cell response, whereas CTLA-4 signaling attenuates it. The CTLA-4 and B7-2 monomers are both two-layer beta-sandwiches that display the chain topology characteristic of the immunoglobulin variable (V-type) domains present in antigen receptors. The front and back sheets of B7-2 are composed of AGFCC'C" and BED strands, respectively. Members of the IgV family are components of immunoglobulin (Ig) and T cell receptors. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. In Ig, each chain is composed of one variable domain (IgV) and one or more constant domains (IgC); these names reflect the fact that the variability in sequences is higher in the variable domain than in the constant domain. Within the variable domain, there are regions of even more variability called the hypervariable or complementarity-determining regions (CDRs) which are responsible for antigen binding. A predominant feature of most Ig domains is the disulfide bridge connecting 2 beta-sheets with a tryptophan residue packed against the disulfide bond.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 665401767 192 TAHVPCTVHH-----IGEGVVSWIRKKDYHLLTVglttYSSDERFSATHLKH-------SEDWTLQIKFVQLRDAGVYEC 259
Cdd:cd16087   10 TAYLPCQFKNpqnisLSELVVFWQDQKKLVLYEL----YLGKEKLDNVNSKYigrtsfdQENWTLQLHNVQIKDQGTYQC 85

                         90       100
                 ....*....|....*....|...
gi 665401767 260 QVSTHPPT-SIFLH-----LSVV 276
Cdd:cd16087   86 FIHHKSPKgLVLIHqmsseLSVI 108

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 665401767 290 TPGSTLRLQCRVVQNTEASEyIFWYHDNRMINYDIdrGINVsTEPDFQSSELTIQRTRREHSGNFTCVASN 360
Cdd:cd20959   15 QVGMRAQLHCGVPGGDLPLN-IRWTLDGQPISDDL--GITV-SRLGRRSSILSIDSLEASHAGNYTCHARN 81

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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 665401767 292 GSTLRLQCRVVQNteASEYIFWYHDNRMINYDIDrgINVSTEPDFQSseLTIQRTRREHSGNFTCVASNT 361
Cdd:cd20972   16 GSKVRLECRVTGN--PTPVVRWFCEGKELQNSPD--IQIHQEGDLHS--LIIAEAFEEDTGRYSCLATNS 79