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 564337054  34 TVTSLPGATVTLICPGKEAAGNATIHWVYSGSQS----REWTTTGNTLVLRAVQVNDTGHYLCFLDDHLVGTVPLLV 106
Cdd:cd20939    1 VLTSLPGASVTLTCPGVEPEDNATIHWVLRKPAAgshpSRWAGMGRRLLLRSVQLSDSGNYSCYRAGRPAGTVHLLV 77

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
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 564337054   213 PDPPANLVVSAIPgrPRWLKVSWQDPESWDPSYYLLQFELRYRPVWSKTFTVwPLQVAQHQCVIHDALRGVKHVVQVR 290
Cdd:smart00060   1 PSPPSNLRVTDVT--STSVTLSWEPPPDDGITGYIVGYRVEYREEGSEWKEV-NVTPSSTSYTLTGLKPGTEYEFRVR 75

Immunoglobulin-like domain D1 of interleukin-6 receptor alpha-chain (IL-6RA, also known as CD126); member of the C2-set of IgSF domains; The members here are composed of the immunoglobulin-like domain D1 of interleukin-6 receptor alpha-chain (IL-6RA, also known as CD126). The IL-6RA ectodomain, which is highly modular, consisting of three domains (D1, D2, and D3). Interleukin-6 (IL-6) is a multifunctional cytokine that regulates the immune response, hemopoiesis, the acute phase response and inflammation. It is generated in an infectious lesion and sends out a warning signal to the entire body. IL-6 binds first to its cognate alpha-chain receptor (IL-6R), and then the IL-6/IL-6R complex which in turn induces homodimerization of gp130. As a result, a high-affinity functional receptor complex of IL-6, IL-6R and gp130 is formed, and subsequently the complex triggers a downstream signal cascade. Aberrant production of IL-6 and its receptor (IL-6R) are implicated in the pathogenesis of multiple myeloma, autoimmune diseases and prostate 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. Unlike other Ig domain sets, the C2-set lacks the D strand.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 564337054  34 TVTSLPGATVTLICPGKEAAGNATIHWVYSGSQS----REWTTTGNTLVLRAVQVNDTGHYLCFLDDHLVGTVPLLV 106
Cdd:cd20939    1 VLTSLPGASVTLTCPGVEPEDNATIHWVLRKPAAgshpSRWAGMGRRLLLRSVQLSDSGNYSCYRAGRPAGTVHLLV 77

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 564337054   30 VANGTVTSLPGATVTLICPGKEAAGNATIHWVYSGSQSRE--------WTTTGNTLVLRAVQVNDTGHYLCFLDDHL 98
Cdd:pfam00047   1 SAPPTVTVLEGDSATLTCSASTGSPGPDVTWSKEGGTLIEslkvkhdnGRTTQSSLLISNVTKEDAGTYTCVVNNPG 77

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 564337054 213 PDPPANLVVSAIPgrPRWLKVSWQDPEswDPSYYLLQFELRYRPVWSKTF-TVWPLQVAQHQCVIHDALRGVKHVVQVRG 291
Cdd:cd00063    1 PSPPTNLRVTDVT--STSVTLSWTPPE--DDGGPITGYVVEYREKGSGDWkEVEVTPGSETSYTLTGLKPGTEYEFRVRA 76

                         90
                 ....*....|....*..
gi 564337054 292 KEEFDIGQWSKWSPEVT 308
Cdd:cd00063   77 VNGGGESPPSESVTVTT 93

Immunoglobulin-like domain D1 of interleukin-6 receptor alpha-chain (IL-6RA, also known as CD126); member of the C2-set of IgSF domains; The members here are composed of the immunoglobulin-like domain D1 of interleukin-6 receptor alpha-chain (IL-6RA, also known as CD126). The IL-6RA ectodomain, which is highly modular, consisting of three domains (D1, D2, and D3). Interleukin-6 (IL-6) is a multifunctional cytokine that regulates the immune response, hemopoiesis, the acute phase response and inflammation. It is generated in an infectious lesion and sends out a warning signal to the entire body. IL-6 binds first to its cognate alpha-chain receptor (IL-6R), and then the IL-6/IL-6R complex which in turn induces homodimerization of gp130. As a result, a high-affinity functional receptor complex of IL-6, IL-6R and gp130 is formed, and subsequently the complex triggers a downstream signal cascade. Aberrant production of IL-6 and its receptor (IL-6R) are implicated in the pathogenesis of multiple myeloma, autoimmune diseases and prostate 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. Unlike other Ig domain sets, the C2-set lacks the D strand.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 564337054  34 TVTSLPGATVTLICPGKEAAGNATIHWVYSGSQS----REWTTTGNTLVLRAVQVNDTGHYLCFLDDHLVGTVPLLV 106
Cdd:cd20939    1 VLTSLPGASVTLTCPGVEPEDNATIHWVLRKPAAgshpSRWAGMGRRLLLRSVQLSDSGNYSCYRAGRPAGTVHLLV 77

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 564337054   30 VANGTVTSLPGATVTLICPGKEAAGNATIHWVYSGSQSRE--------WTTTGNTLVLRAVQVNDTGHYLCFLDDHL 98
Cdd:pfam00047   1 SAPPTVTVLEGDSATLTCSASTGSPGPDVTWSKEGGTLIEslkvkhdnGRTTQSSLLISNVTKEDAGTYTCVVNNPG 77

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 564337054 213 PDPPANLVVSAIPgrPRWLKVSWQDPEswDPSYYLLQFELRYRPVWSKTF-TVWPLQVAQHQCVIHDALRGVKHVVQVRG 291
Cdd:cd00063    1 PSPPTNLRVTDVT--STSVTLSWTPPE--DDGGPITGYVVEYREKGSGDWkEVEVTPGSETSYTLTGLKPGTEYEFRVRA 76

                         90
                 ....*....|....*..
gi 564337054 292 KEEFDIGQWSKWSPEVT 308
Cdd:cd00063   77 VNGGGESPPSESVTVTT 93

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 564337054   34 TVTSLPGATVTLICpgkEAAGN--ATIHWVYSG-------SQSREWTTTGNTLVLRAVQVNDTGHYLC 92
Cdd:pfam13927  10 SVTVREGETVTLTC---EATGSppPTITWYKNGepissgsTRSRSLSGSNSTLTISNVTRSDAGTYTC 74

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 564337054  32 NGTVTSLPGATVTLICpgkEAAGNA--TIHWVYSG-------SQSREWTTTGNTLVLRAVQVNDTGHYLC 92
Cdd:cd20969    9 AQQVFVDEGHTVQFVC---RADGDPppAILWLSPRkhlvsakSNGRLTVFPDGTLEVRYAQVQDNGTYLC 75