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 2217327623   1 MEFFKNENNELPKLQWYKDCKPLLLDNIHFSGVKDRLIVMNVAEKHRGNYTCHASYTYLGKQYPITRVIEFITLE 75
Cdd:cd20994    20 LDFFKDENNNLPKVQWYKDCKPLLLDDKRFAGLESDLLIFNVTVQDQGNYTCHTSYTYMGKQYNISRTISLIVLE 94

Second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R), and similar domains; The members here are composed of the second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R). IL-1 alpha and IL-1 beta are cytokines which participate in the regulation of inflammation, immune responses, and hematopoiesis. These cytokines bind to the IL-1 receptor type 1 (IL1R1), which is activated on additional association with interleukin-1 receptor accessory protein (IL1RAP). IL-1 also binds a second receptor designated type II (IL1R2). Mature IL1R1 consists of three IG-like domains, a transmembrane domain, and a large cytoplasmic domain. Mature IL1R2 is organized similarly except that it has a short cytoplasmic domain. The latter does not initiate signal transduction. A naturally occurring cytokine IL-1RA (IL-1 receptor antagonist) is widely expressed and binds to IL-1 receptors, inhibiting the binding of IL-1 alpha and IL-1 beta. This group also contains ILIR-like 1 (IL1R1L) which maps to the same chromosomal location as IL1R1 and IL1R2.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217327623   1 MEFFKNENNELPKLQWYKDCKPLLLDNIHFSGVKDRLIVMNVAEKHRGNYTCHASYTYLGKQYPITRVIEFITLE 75
Cdd:cd20994    20 LDFFKDENNNLPKVQWYKDCKPLLLDDKRFAGLESDLLIFNVTVQDQGNYTCHTSYTYMGKQYNISRTISLIVLE 94

TIR domain; The Toll/interleukin-1 receptor (TIR) homology domain is an intracellular signalling domain found in MyD88, interleukin 1 receptor and the Toll receptor. It contains three highly-conserved regions, and mediates protein-protein interactions between the Toll-like receptors (TLRs) and signal-transduction components. TIR-like motifs are also found in plant proteins thought to be involved in resistance to disease. When activated, TIR domains recruit cytoplasmic adaptor proteins MyD88 and TOLLIP (Toll interacting protein). In turn, these associate with various kinases to set off signalling cascades.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217327623 244 YILYPKTVGEGSTsdcDIFVFKVLPEVleKQCGYKLFIYGRDDYVGEDIVEVINENVKKSRRLIIILVRETSGFSW-Lgg 322
Cdd:pfam01582   1 YDVFLSFRGSDTR---EWFVSHLLKEL--KQKGIKLFIDDRDLEPGEAIAPELLSAIEKSRRSVVVLSPNYASSGWcL-- 73

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217327623 323 sSEEQIAMYNALvQDGIKVVLLELEKIQDYE-----KMPESIKFIKQKH---GAIRWSGDFTQGP-------QSAKTRFW 387
Cdd:pfam01582  74 -DELVKILECAL-DLGQKVIPIFYEVDPSDVrkqtgSFGKAFKKHKKVLteeKVLKWRGALNEVAniwhsksVSDESKFW 151

                  ....*..
gi 2217327623 388 KNVRYHM 394
Cdd:pfam01582 152 KKIAYDI 158

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

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217327623   90 ETMEVDLGSQIQLICNVTGQLSDIAYWKWNGsvideDDPVLGEDYYSVENpaNKRRSTLiTVLNISEIESRFYkhpfTCF 169
Cdd:smart00410   2 PSVTVKEGESVTLSCEASGSPPPEVTWYKQG-----GKLLAESGRFSVSR--SGSTSTL-TISNVTPEDSGTY----TCA 69

                           90
                   ....*....|....*
gi 2217327623  170 AKNTHGIDAAYIQLI 184
Cdd:smart00410  70 ATNSSGSASSGTTLT 84

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217327623  81 RPVIVSPaNETMEVDLGSQIQLICNVTGQLSDIAYWKWNGSVIDEDDpvlgedyySVENPANKRRSTLiTVLNISEIESR 160
Cdd:pfam13927   1 KPVITVS-PSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGS--------TRSRSLSGSNSTL-TISNVTRSDAG 70

                          90
                  ....*....|..
gi 2217327623 161 FYkhpfTCFAKN 172
Cdd:pfam13927  71 TY----TCVASN 78

Second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R), and similar domains; The members here are composed of the second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R). IL-1 alpha and IL-1 beta are cytokines which participate in the regulation of inflammation, immune responses, and hematopoiesis. These cytokines bind to the IL-1 receptor type 1 (IL1R1), which is activated on additional association with interleukin-1 receptor accessory protein (IL1RAP). IL-1 also binds a second receptor designated type II (IL1R2). Mature IL1R1 consists of three IG-like domains, a transmembrane domain, and a large cytoplasmic domain. Mature IL1R2 is organized similarly except that it has a short cytoplasmic domain. The latter does not initiate signal transduction. A naturally occurring cytokine IL-1RA (IL-1 receptor antagonist) is widely expressed and binds to IL-1 receptors, inhibiting the binding of IL-1 alpha and IL-1 beta. This group also contains ILIR-like 1 (IL1R1L) which maps to the same chromosomal location as IL1R1 and IL1R2.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217327623   1 MEFFKNENNELPKLQWYKDCKPLLLDNIHFSGVKDRLIVMNVAEKHRGNYTCHASYTYLGKQYPITRVIEFITLE 75
Cdd:cd20994    20 LDFFKDENNNLPKVQWYKDCKPLLLDDKRFAGLESDLLIFNVTVQDQGNYTCHTSYTYMGKQYNISRTISLIVLE 94

Second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R), and similar domains; The members here are composed of the second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R; also known as cluster of differentiation (CD) 121). IL-1 alpha and IL-1 beta are cytokines which participate in the regulation of inflammation, immune responses, and hematopoiesis. These cytokines bind to the IL-1 receptor type 1 (IL1R1), which is activated on additional association with interleukin-1 receptor accessory protein (IL1RAP). IL-1 also binds a second receptor designated type II (IL1R2). Mature IL1R1 consists of three IG-like domains, a transmembrane domain, and a large cytoplasmic domain. Mature IL1R2 is organized similarly except that it has a short cytoplasmic domain. The latter does not initiate signal transduction. A naturally occurring cytokine IL-1RA (IL-1 receptor antagonist) is widely expressed and binds to IL-1 receptors, inhibiting the binding of IL-1 alpha and IL-1 beta. This group also contains ILIR-like 1 (IL1R1L) which maps to the same chromosomal location as IL1R1 and IL1R2.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2217327623   1 MEFFKNENNeLPKLQWYKDCKPLLLDNiHFSGVKDRLIVMNVAEKHRGNYTCHASYTYLGKQYPITRVIEFITLE 75
Cdd:cd05757    20 LDDYKNENV-LPPIQWYKDCKPLQGDK-RFIPKGSKLLIQNVTEEDAGNYTCKFTYTHNGKQYNVTRTISLTVTE 92

Second immunoglobulin (Ig)-like domain of interleukin-1 receptor-2 (IL1R2), and similar domains; The members here are composed of the second immunoglobulin (Ig)-like domain of interleukin-1 receptor-2 (IL1R2). IL-1 alpha and IL-1 beta are cytokines which participate in the regulation of inflammation, immune responses, and hematopoiesis. These cytokines bind to the IL-1 receptor type 1 (IL1R1), which is activated on additional association with interleukin-1 receptor accessory protein (IL1RAP). IL-1 also binds the IL-1 receptor, type II (IL1R2) represented in this group. Mature IL1R2 consists of three IG-like domains, a transmembrane domain, and a short cytoplasmic domain. It lacks the large cytoplasmic domain of mature IL1R1 and does not initiate signal transduction. A naturally occurring cytokine IL-1RA (IL-1 receptor antagonist) is widely expressed and binds to IL-1 receptors, inhibiting the binding of IL-1 alpha and IL-1 beta.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2217327623   2 EFFKNENNElpKLQWYKDCKPLLLDNIHFSGVKDR--LIVMNVAEKHRGNYTCHASYTYLGKQYPITRVIEFITLE 75
Cdd:cd05897    22 EFTINRTDV--EIQWYKDSLLLDKDNEKFLSVKGSthLLIHDVSLNDSGYYTCKLTFTHEGKKYNITRSIELRIVK 95

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
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 2217327623   7 ENNELPKLQWYKDCKPLLLD---NIHFSGVKDRLIVMNVAEKHRGNYTCHASYTYLGKQ 62
Cdd:cd00096     8 SGNPPPTITWYKNGKPLPPSsrdSRRSELGNGTLTISNVTLEDSGTYTCVASNSAGGSA 66

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217327623   8 NNELPKLQWYKDCKPLlldnihfsGVKDRLIVMNVAEKHRGNYTCHASYTYLGKQYPITRVI 69
Cdd:pfam13895  25 GNPPPSYTWYKDGSAI--------SSSPNFFTLSVSAEDSGTYTCVARNGRGGKVSNPVELT 78

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 2217327623  12 PKLQWYKD---CKPLLLDNIHFSGVKDRLIVMNVAEKHRGNYTCHAS 55
Cdd:pfam13927  31 PTITWYKNgepISSGSTRSRSLSGSNSTLTISNVTRSDAGTYTCVAS 77

Immunoglobulin-like domain of human nephrin and similar proteins; member of the C1-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin-like domain in human nephrin and similar proteins. Nephrin is an integral component of the slit diaphragm and is a central component of the glomerular ultrafilter. Nephrin plays a structural role and has a role in signaling. Nephrin is a transmembrane protein having a short intracellular portion, an extracellular portion comprised of eight Ig-like domains, and one fibronectin type III-like domain. The extracellular portions of nephrin from neighboring foot processes of separate podocyte cells may interact with each other, and in association with other components of the slit diaphragm form a porous molecular sieve within the slit pore. The intracellular portion of nephrin is associated with linker proteins, which connect nephrin to the actin cytoskeleton. The intracellular portion is tyrosine phosphorylated, and mediates signaling from the slit diaphragm into the podocytes.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217327623  95 DLGSQIQLICNVTGQLSDIAYWKWNGSVIDEDDPVLGEDYYSvenpANKRRSTLITVLNISEIESRFYkhpFTCFAKNTH 174
Cdd:cd05773    21 DGSSDANLVCQAQGVPRVQFRWAKNGVPLDLGNPRYEETTEH----TGTVHTSILTIINVSAALDYAL---FTCTAHNSL 93

                          90
                  ....*....|
gi 2217327623 175 GIDAAYIQLI 184
Cdd:cd05773    94 GEDSLDIQLV 103

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor (VEGFR); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor (VEGFR). The VEGFRs have an extracellular component with seven Ig-like domains, a transmembrane segment, and an intracellular tyrosine kinase domain interrupted by a kinase-insert domain. The VEGFR family consists of three members, VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), and VEGFR-3 (Flt-4). VEGFRs bind VEGFs with high affinity at the Ig-like domains. VEGF-A is important to the growth and maintenance of vascular endothelial cells and to the development of new blood- and lymphatic-vessels in physiological and pathological states. VEGFR-2 is a major mediator of the mitogenic, angiogenic, and microvascular permeability-enhancing effects of VEGF-A. VEGFR-1 may play an inhibitory part in these processes by binding VEGF and interfering with its interaction with VEGFR-2. VEGFR-1 has a signaling role in mediating monocyte chemotaxis. VEGFR-1 and VEGFR-2 may mediate a chemotactic and a survival signal in hematopoietic stem cells or leukemia cells. VEGFR-3 has been shown to be involved in tumor angiogenesis and growth. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 2217327623  12 PKLQWYKDCKPLLLDNIHFSGvkDRLIVMNVAEKHRGNYT 51
Cdd:cd04976    33 PEVVWYKDGLPLTEKARYLTR--HSLIIKEVTEEDTGNYT 70