Death domain found in Uncoordinated-5A; Death Domain (DD) found in Uncoordinated-5A (UNC5A). UNC5A is part of the UNC-5 homolog family. It is a receptor for the secreted netrin-1 and plays a critical role in neuronal development and differentiation, as well as axon-guidance. It also plays a role in regulating apoptosis in non-neuronal cells as a downstream target of p53. UNC5 proteins are transmembrane proteins with an extracellular domain consisting of two immunoglobulin repeats, two thrombospondin type-I modules and an intracellular region containing a ZU-5 domain, UPA domain and a DD. In general, DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily including CARD (Caspase activation and recruitment domain), DED (Death Effector Domain), and PYRIN. They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178 755 IPFLIRQKIIASLDPPCSRGADWRTLAQKLHLDSHLSFFASKPSPTAMILNLWEARHFPNGNLGQLAAAVAGLGQPDAGL 834
Cdd:cd08800    1 IPFLIRQKIISSLDPPCPRGADWRTLAQKLNLDSHLSFFASKSSPTAMILNLWEAQHFPNGNLSQLAAVVAEIGKQDAML 80

                 ....
gi 672081178 835 FTVS 838
Cdd:cd08800   81 FLVS 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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178 153 QEPLAKEVSLEQGIVLPCRPPEGIPPAEVEWLRNEDLVDpSLDPNVYITREHSLVVRQARLADTANYTCVAKNIVARRRS 232
Cdd:cd05724    2 VEPSDTQVAVGEMAVLECSPPRGHPEPTVSWRKDGQPLN-LDNERVRIVDDGNLLIAEARKSDEGTYKCVATNMVGERES 80

                 ....*..
gi 672081178 233 TSAAVIV 239
Cdd:cd05724   81 RAARLSV 87

Death domain found in Uncoordinated-5A; Death Domain (DD) found in Uncoordinated-5A (UNC5A). UNC5A is part of the UNC-5 homolog family. It is a receptor for the secreted netrin-1 and plays a critical role in neuronal development and differentiation, as well as axon-guidance. It also plays a role in regulating apoptosis in non-neuronal cells as a downstream target of p53. UNC5 proteins are transmembrane proteins with an extracellular domain consisting of two immunoglobulin repeats, two thrombospondin type-I modules and an intracellular region containing a ZU-5 domain, UPA domain and a DD. In general, DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily including CARD (Caspase activation and recruitment domain), DED (Death Effector Domain), and PYRIN. They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178 755 IPFLIRQKIIASLDPPCSRGADWRTLAQKLHLDSHLSFFASKPSPTAMILNLWEARHFPNGNLGQLAAAVAGLGQPDAGL 834
Cdd:cd08800    1 IPFLIRQKIISSLDPPCPRGADWRTLAQKLNLDSHLSFFASKSSPTAMILNLWEAQHFPNGNLSQLAAVVAEIGKQDAML 80

                 ....
gi 672081178 835 FTVS 838
Cdd:cd08800   81 FLVS 84

ZU5 domain; Domain present in ZO-1 and Unc5-like netrin receptors Domain of unknown function.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178  443 AYGTFNFLGGRLMIPNTGISLLIPPDAIPRGKIYEIYLTLHKPEDVRLPLAGCQTLLSPVVSCGPPGVLLTRPVILAMDH 522
Cdd:pfam00791   1 VSGLVDSRGGRLVLPNSGVSLLIPPGAIPEGTRIECYLAVNRDESSRPPLEEGETLLSPVVECGPPGLKFLKPVILEVPH 80

                          90
                  ....*....|....*..
gi 672081178  523 CGEPSPDSWSLRLKKQS 539
Cdd:pfam00791  81 CASLRPEEWEIVLKRSD 97

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. 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 672081178 153 QEPLAKEVSLEQGIVLPCRPPEGIPPAEVEWLRNEDLVDpSLDPNVYITREHSLVVRQARLADTANYTCVAKNIVARRRS 232
Cdd:cd05724    2 VEPSDTQVAVGEMAVLECSPPRGHPEPTVSWRKDGQPLN-LDNERVRIVDDGNLLIAEARKSDEGTYKCVATNMVGERES 80

                 ....*..
gi 672081178 233 TSAAVIV 239
Cdd:cd05724   81 RAARLSV 87

Immunoglobulin I-set domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178  151 FEQEPLAKEVSLEQGIVLPCRPpEGIPPAEVEWLRNEDLVDPSldPNVYITRE---HSLVVRQARLADTANYTCVAKNIV 227
Cdd:pfam07679   3 FTQKPKDVEVQEGESARFTCTV-TGTPDPEVSWFKDGQPLRSS--DRFKVTYEggtYTLTISNVQPDDSGKYTCVATNSA 79

                          90
                  ....*....|..
gi 672081178  228 ArRRSTSAAVIV 239
Cdd:pfam07679  80 G-EAEASAELTV 90

Thrombospondin type 1 repeats; Type 1 repeats in thrombospondin-1 bind and activate TGF-beta.

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*.
gi 672081178   251 WSACGLDC---THWRSRECSDPAPRNGGEECRGADLDTRNCTSDLC 293
Cdd:smart00209   7 WSPCSVTCgggVQTRTRSCCSPPPQNGGGPCTGEDVETRACNEQPC 52

Death domain found in Uncoordinated-5A; Death Domain (DD) found in Uncoordinated-5A (UNC5A). UNC5A is part of the UNC-5 homolog family. It is a receptor for the secreted netrin-1 and plays a critical role in neuronal development and differentiation, as well as axon-guidance. It also plays a role in regulating apoptosis in non-neuronal cells as a downstream target of p53. UNC5 proteins are transmembrane proteins with an extracellular domain consisting of two immunoglobulin repeats, two thrombospondin type-I modules and an intracellular region containing a ZU-5 domain, UPA domain and a DD. In general, DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily including CARD (Caspase activation and recruitment domain), DED (Death Effector Domain), and PYRIN. They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178 755 IPFLIRQKIIASLDPPCSRGADWRTLAQKLHLDSHLSFFASKPSPTAMILNLWEARHFPNGNLGQLAAAVAGLGQPDAGL 834
Cdd:cd08800    1 IPFLIRQKIISSLDPPCPRGADWRTLAQKLNLDSHLSFFASKSSPTAMILNLWEAQHFPNGNLSQLAAVVAEIGKQDAML 80

                 ....
gi 672081178 835 FTVS 838
Cdd:cd08800   81 FLVS 84

ZU5 domain; Domain present in ZO-1 and Unc5-like netrin receptors Domain of unknown function.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178  443 AYGTFNFLGGRLMIPNTGISLLIPPDAIPRGKIYEIYLTLHKPEDVRLPLAGCQTLLSPVVSCGPPGVLLTRPVILAMDH 522
Cdd:pfam00791   1 VSGLVDSRGGRLVLPNSGVSLLIPPGAIPEGTRIECYLAVNRDESSRPPLEEGETLLSPVVECGPPGLKFLKPVILEVPH 80

                          90
                  ....*....|....*..
gi 672081178  523 CGEPSPDSWSLRLKKQS 539
Cdd:pfam00791  81 CASLRPEEWEIVLKRSD 97

Death domain found in Uncoordinated-5C; Death Domain (DD) found in Uncoordinated-5C (UNC5C). UNC5C is part of the UNC-5 homolog family. It is a receptor for the secreted netrin-1 and plays a role in axonal guidance, angiogenesis, and apoptosis. UNC5C plays a critical role in the development of spinal accessory motor neurons. Methylation of the UNC5C gene is associated with early stages of colorectal carcinogenesis. UNC5 proteins are transmembrane proteins with an extracellular domain consisting of two immunoglobulin repeats, two thrombospondin type-I modules and an intracellular region containing a ZU-5 domain, UPA domain and a DD. In general, DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily including CARD (Caspase activation and recruitment domain), DED (Death Effector Domain), and PYRIN. They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 672081178 755 IPFLIRQKIIASLDPPCSRGADWRTLAQKLHLDSHLSFFASKPSPTAMILNLWEARHFPNGNLGQLAAAVAGLGQPDA 832
Cdd:cd08799    1 IPLSIRQKLCGSLDAPQTRGNDWRMLAHKLNLDRYLNYFATKSSPTGVILDLWEAQHFPDGNLSRLAAVLEEMGRHET 78

Death domain found in Uncoordinated-5D; Death Domain (DD) found in Uncoordinated-5D (UNC5D). UNC5D is part of the UNC-5 homolog family. It is a receptor for the secreted netrin-1 and plays a role in axonal guidance, angiogenesis, and apoptosis. UNC5 proteins are transmembrane proteins with an extracellular domain consisting of two immunoglobulin repeats, two thrombospondin type-I modules and an intracellular region containing a ZU-5 domain, UPA domain and a DD. In general, DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily including CARD (Caspase activation and recruitment domain), DED (Death Effector Domain), and PYRIN. They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178 755 IPFLIRQKIIASLDPPCSRGADWRTLAQKLHLDSHLSFFASKPSPTAMILNLWEARHFPNGNLGQLAAAVAGLGQPDAGL 834
Cdd:cd08801    1 IPYSIRQRICATFDTPNAKGKDWQMLAQKNSIDRNLSYFATQSSPSAVILSLWEARHQHDGDLDSLACALEEIGRTHSKQ 80

                 ....*..
gi 672081178 835 FTVSEAE 841
Cdd:cd08801   81 STIAETL 87

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. 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 672081178 153 QEPLAKEVSLEQGIVLPCRPPEGIPPAEVEWLRNEDLVDpSLDPNVYITREHSLVVRQARLADTANYTCVAKNIVARRRS 232
Cdd:cd05724    2 VEPSDTQVAVGEMAVLECSPPRGHPEPTVSWRKDGQPLN-LDNERVRIVDDGNLLIAEARKSDEGTYKCVATNMVGERES 80

                 ....*..
gi 672081178 233 TSAAVIV 239
Cdd:cd05724   81 RAARLSV 87

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band 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. 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 Ig I1 domain of the titin I-band 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 (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 672081178 174 EGIPPAEVEWLRNEDLVDPSLDPNVYITRE----HSLVVRQARLADTANYTCVAKNIvARRRSTSAAVIV 239
Cdd:cd20951   25 QGKPDPEVKWYKNGVPIDPSSIPGKYKIESeygvHVLHIRRVTVEDSAVYSAVAKNI-HGEASSSASVVV 93

Death domain of Myeloid Differentation primary response protein MyD88; Death Domain (DD) of Myeloid Differentiation primary response protein 88 (MyD88). MyD88 is an adaptor protein involved in interleukin-1 receptor (IL-1R)- and Toll-like receptor (TLR)-induced activation of nuclear factor-kappaB (NF-kB) and mitogen activated protein kinase pathways that lead to the induction of proinflammatory cytokines. It is a key component in the signaling pathway of pathogen recognition in the innate immune system. MyD88 contains an N-terminal DD and a C-terminal Toll/IL-1 Receptor (TIR) homology domain that mediates interaction with TLRs and IL-1R. In general, DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily including CARD (Caspase activation and recruitment domain), DED (Death Effector Domain), and PYRIN. They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 672081178 760 RQKIIASLDPPCSRGADWRTLAQKLHLDS-HLSFFASKPSPTAMILNLWEARHfPNGNLGQL 820
Cdd:cd08312    2 RKKLSLYLNPEKVVANDWRGLAELMGFDYlEIRNFERQSSPTERLLEDWETRP-PGATVGNL 62

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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178 150 NFEQEPLAKEVSLEQGIVLPCRPpEGIPPAEVEWLRNEDLVDPSLDPNVYITRE-HSLVVRQARLADTANYTCVAKNIVA 228
Cdd:cd20972    3 QFIQKLRSQEVAEGSKVRLECRV-TGNPTPVVRWFCEGKELQNSPDIQIHQEGDlHSLIIAEAFEEDTGRYSCLATNSVG 81

                         90
                 ....*....|.
gi 672081178 229 rRRSTSAAVIV 239
Cdd:cd20972   82 -SDTTSAEIFV 91

Death domain of Nuclear Factor-KappaB precursor proteins; Death Domain (DD) of Nuclear Factor-KappaB (NF-kB) precursor proteins. The NF-kB family of transcription factors play a central role in cardiovascular growth, stress response, and inflammation by controlling the expression of a network of different genes. There are five NF-kB proteins, all containing an N-terminal REL Homology Domain (RHD). Two of these, NF-kB1 and NF-kB2 are produced from the processing of the precursor proteins p105 and p100, respectively. In addition to RHD, p105 and p100 contain ANK repeats and a C-terminal DD. NF-kBs are regulated by the Inhibitor of NF-kB (IkB) Kinase (IKK) complex through classical and non-canonical pathways, which differ in the IKK subunits involved and downstream targets. IKKs facilitate the release of NF-kB dimers from an inactive state, allowing them to migrate to the nucleus where they regulate gene transcription. The precursor proteins p105 and p100 function as IkBs and as NF-kB proteins after being processed by the proteasome. In general, DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily including CARD (Caspase activation and recruitment domain), DED (Death Effector Domain), and PYRIN. They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 672081178 767 LDPPCsrgaDWRTLAQKLHLDSHLSFFASKPSPTAMILNLWEARhfpNGNLGQLAAAVAGLGQPDA 832
Cdd:cd08310    9 LDVGK----DWRELAELLGLGHLVESIEQSSSPTKLLLDYYEAQ---GGTLEKLREALRALGETDA 67

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 672081178  166 IVLPCRPpEGIPPAEVEWLRNEDLVDPSLDPNVYITREHS-LVVRQARLADTANYTCVAKN 225
Cdd:pfam13927  19 VTLTCEA-TGSPPPTITWYKNGEPISSGSTRSRSLSGSNStLTISNVTRSDAGTYTCVASN 78

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

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 672081178   166 IVLPCRPPeGIPPAEVEWLRNeDLVDPSLDPNVYITRE---HSLVVRQARLADTANYTCVAKN 225
Cdd:smart00410  12 VTLSCEAS-GSPPPEVTWYKQ-GGKLLAESGRFSVSRSgstSTLTISNVTPEDSGTYTCAATN 72

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 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 (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 672081178 151 FEQEPLAKEVSLEQGIVLPCRPpEGIPPAEVEWLRNEDLVdPSLDPNVYITREHSLVVRQARLADTANYTCVAKNIvarr 230
Cdd:cd20952    2 ILQGPQNQTVAVGGTVVLNCQA-TGEPVPTISWLKDGVPL-LGKDERITTLENGSLQIKGAEKSDTGEYTCVALNL---- 75

                         90
                 ....*....|..
gi 672081178 231 rSTSAAVIVYVD 242
Cdd:cd20952   76 -SGEATWSAVLD 86

Second immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins. L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, 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, or spastic paraplegia type 1 that involves abnormalities of axonal 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        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 672081178 158 KEVSLEQG--IVLPCRPPEGIPPAEVEWLrNEDLVDPSLDPNVYITREHSLVVRQARLADTAN-YTCVA 223
Cdd:cd05845    5 DPVEVEEGdpVVLPCNPPKGAPPPRIYWM-NSSLEHITQDERVSMGQNGDLYFSNVMEQDSHPdYICHA 72

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. 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.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178 154 EPLAKEVSLEQGIVLPCRPpEGIPPAEVEWlRNEDLVDPslDPNVYITREHSLVVRQARLADTANYTCVAKNIVArRRST 233
Cdd:cd05725    3 RPQNQVVLVDDSAEFQCEV-GGDPVPTVRW-RKEDGELP--KGRYEILDDHSLKIRKVTAGDMGSYTCVAENMVG-KIEA 77

                 ....*.
gi 672081178 234 SAAVIV 239
Cdd:cd05725   78 SATLTV 83

Second Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the second Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 672081178 165 GIVLPCRPPEGIPPAEVEWLRNEDLVDPSLDPNVYITREH-SLVVRQARLADTANYTCVAKNIV 227
Cdd:cd05727   12 GVVLFCDPPPHYPDLSYRWLLNEFPNFIPEDGRRFVSQTNgNLYIAKVEASDRGNYSCFVSSPS 75

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178  159 EVSLEQGIVLPCRPPEGIPPAEVEWLRnEDLVDPSLD---PNVYITREHSLVVRQARLADTANYTCVAKN 225
Cdd:pfam00047   7 TVLEGDSATLTCSASTGSPGPDVTWSK-EGGTLIESLkvkHDNGRTTQSSLLISNVTKEDAGTYTCVVNN 75

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672081178 153 QEPLAKEVSLEQGIVLPCRPpEGIPPAEVEWLRNedlvDPSLDPNVYITREHSLVVRQARLADTANYTCVAKNIVAR-RR 231
Cdd:cd04976    8 KQQVLEATAGKRSVRLPMKV-KAYPPPEVVWYKD----GLPLTEKARYLTRHSLIIKEVTEEDTGNYTILLSNKQSNvFK 82

                 ....*...
gi 672081178 232 STSAAVIV 239
Cdd:cd04976   83 NLTATLVV 90

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.

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gi 672081178 156 LAKEVSLEQG--IVLPCRPpEGIPPAEVEWL-RNEDLVDPSLDPNVYITREHSLVVRQARLADTANYTCVAKN 225
Cdd:cd20969    8 KAQQVFVDEGhtVQFVCRA-DGDPPPAILWLsPRKHLVSAKSNGRLTVFPDGTLEVRYAQVQDNGTYLCIAAN 79

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor 2 (VEGFR-2); 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 2 (VEGFR-2). 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. VEGFRs bind VEGFs with high affinity at the Ig-like domains. VEGFR-2 (KDR/Flk-1) is a major mediator of the mitogenic, angiogenic and microvascular permeability-enhancing effects of VEGF-A; 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. VEGF-A also interacts with VEGFR-1, which it binds more strongly than VEGFR-2. VEGFR-1 and VEGFR-2 may mediate a chemotactic and a survival signal in hematopoietic stem cells or leukemia cells. 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.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 672081178 175 GIPPAEVEWLRNEDLvdpsLDPNVYITREHSLVVRQARLADTANYTCVAKN 225
Cdd:cd05864   28 GYPPPEIKWYKNGIP----IESNHTIKAGHVLTIMEVTEKDAGNYTVVLTN 74