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

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2183707411  123 PVAVYTWEGNQVNITCEVFAYPSATISWFRDGQLLPSSNySNIKIYNTPSASYLEVTPDSENDFGNYNCTAVNRIGQES 201
Cdd:smart00410   1 PPSVTVKEGESVTLSCEASGSPPPEVTWYKQGGKLLAES-GRFSVSRSGSTSTLTISNVTPEDSGTYTCAATNSSGSAS 78

Fibronectin type III domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411 213 SSPSIDQVEP-YSSTAQVQFDEPEaTGGVPILKYKAEWRAVGEEvWHSKWYDAKEASMEgiVTIVGLKPETTYAVRLAAL 291
Cdd:pfam00041   1 SAPSNLTVTDvTSTSLTVSWTPPP-DGNGPITGYEVEYRPKNSG-EPWNEITVPGTTTS--VTLTGLKPGTEYEVRVQAV 76

                  ....*....
gi 2183707411 292 NGKGLGEIS 300
Cdd:pfam00041  77 NGGGEGPPS 85

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411  19 KPKITYVENQTAMELEEQVTLTCEASGDPIPSITWRTSTRNISSEEktldgHMVVRSHARVSSLTLKSIQYTDAGEYICT 98
Cdd:pfam13927   1 KPVITVSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGS-----TRSRSLSGSNSTLTISNVTRSDAGTYTCV 75

                  ...
gi 2183707411  99 ASN 101
Cdd:pfam13927  76 ASN 78

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

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2183707411  123 PVAVYTWEGNQVNITCEVFAYPSATISWFRDGQLLPSSNySNIKIYNTPSASYLEVTPDSENDFGNYNCTAVNRIGQES 201
Cdd:smart00410   1 PPSVTVKEGESVTLSCEASGSPPPEVTWYKQGGKLLAES-GRFSVSRSGSTSTLTISNVTPEDSGTYTCAATNSSGSAS 78

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 2183707411 134 VNITCEVFAYPSATISWFRDGQLLPSSNYSNIKIYNTPsaSYLEVTPDSENDFGNYNCTAVNRIG 198
Cdd:cd00096     1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELGN--GTLTISNVTLEDSGTYTCVASNSAG 63

Fibronectin type III domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411 213 SSPSIDQVEP-YSSTAQVQFDEPEaTGGVPILKYKAEWRAVGEEvWHSKWYDAKEASMEgiVTIVGLKPETTYAVRLAAL 291
Cdd:pfam00041   1 SAPSNLTVTDvTSTSLTVSWTPPP-DGNGPITGYEVEYRPKNSG-EPWNEITVPGTTTS--VTLTGLKPGTEYEVRVQAV 76

                  ....*....
gi 2183707411 292 NGKGLGEIS 300
Cdd:pfam00041  77 NGGGEGPPS 85

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        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411  212 PSSPSIDQVEPYSST-AQVQFDEPEATGGV-PILKYKAEWRAVGEEvwhskWYDAKEASMEGIVTIVGLKPETTYAVRLA 289
Cdd:smart00060   1 PSPPSNLRVTDVTSTsVTLSWEPPPDDGITgYIVGYRVEYREEGSE-----WKEVNVTPSSTSYTLTGLKPGTEYEFRVR 75

                   ....*...
gi 2183707411  290 ALNGKGLG 297
Cdd:smart00060  76 AVNGAGEG 83

DNA polymerase III subunit gamma/tau;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411 615 DTPTSTPAASNLSSSVLANQGAVLSPSAPAGVGEASKAPPASKPTPAPVPTPTGAASPLAAAAAPATEAPQAK----QEA 690
Cdd:PRK12323  371 GAGPATAAAAPVAQPAPAAAAPAAAAPAPAAPPAAPAAAPAAAAAARAVAAAPARRSPAPEALAAARQASARGpggaPAP 450

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411 691 PSTKGPDPEPTQPGAAKSPAEAATALASPKSEAASVSTTNPSQG-----EDFKMDEGNFKTPDIDLAKDVFAALGSPAPA 765
Cdd:PRK12323  451 APAPAAAPAAAARPAAAGPRPVAAAAAAAPARAAPAAAPAPADDdpppwEELPPEFASPAPAQPDAAPAGWVAESIPDPA 530

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|....*.
gi 2183707411 766 -AGASGQAPELAPSTADSSVSPAPAKTEKGPVEAKPECQETETKPA 810
Cdd:PRK12323  531 tADPDDAFETLAPAPAAAPAPRAAAATEPVVAPRPPRASASGLPDM 576

Herpes virus major outer envelope glycoprotein (BLLF1); This family consists of the BLLF1 viral late glycoprotein, also termed gp350/220. It is the most abundantly expressed glycoprotein in the viral envelope of the Herpesviruses and is the major antigen responsible for stimulating the production of neutralising antibodies in vivo.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411 536 VTTVTTNSDTITET--FATAQNSPTSETTTLTSSIAPPATAT--PDSNSVPAGQATPSkgpsASAPSPAPASAPKVAPLV 611
Cdd:pfam05109 405 ITRTATNATTTTHKviFSKAPESTTTSPTLNTTGFAAPNTTTglPSSTHVPTNLTAPA----STGPTVSTADVTSPTPAG 480

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411 612 DLSDTPTSTPAASNLSSSVLANQGAVLSPSAPAGVGEASKAPPASKPTPAPVPTPTGAASPLAAAAAPATEAPQAKQEAP 691
Cdd:pfam05109 481 TTSGASPVTPSPSPRDNGTESKAPDMTSPTSAVTTPTPNATSPTPAVTTPTPNATSPTLGKTSPTSAVTTPTPNATSPTP 560

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411 692 STKGPDPEPTQPGAAKSPAEAATALASPKSEAASVSTTNPSQGEDFKMDEGNFKTP-----------DIDLAKDVFAALG 760
Cdd:pfam05109 561 AVTTPTPNATIPTLGKTSPTSAVTTPTPNATSPTVGETSPQANTTNHTLGGTSSTPvvtsppknatsAVTTGQHNITSSS 640

                         250       260       270       280       290
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 2183707411 761 SPAPAAGASGQAPELAPSTADSSVSPAPAKTekgpvEAKPECQETETKPAPAEVKT 816
Cdd:pfam05109 641 TSSMSLRPSSISETLSPSTSDNSTSHMPLLT-----SAHPTGGENITQVTPASTST 691

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411  18 AKPKITYVENQTAMELEeQVTLTCEASGDPIPSITWRTSTRNISSEEKTLDGHMVVRSHARVSSLTLKSIQYTDAGEYIC 97
Cdd:cd05732     1 VQPKITYLENQTAVELE-QITLTCEAEGDPIPEITWRRATRGISFEEGDLDGRIVVRGHARVSSLTLKDVQLTDAGRYDC 79

                          90
                  ....*....|....*..
gi 2183707411  98 TASNTIGQDSQSMYLEV 114
Cdd:cd05732    80 EASNRIGGDQQSMYLEV 96

Immunoglobulin domain; This family contains immunoglobulin-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411  19 KPKITYVENQTAMELEEQVTLTCEASGDPIPSITWRTSTRNISSEEktldgHMVVRSHARVSSLTLKSIQYTDAGEYICT 98
Cdd:pfam13927   1 KPVITVSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGS-----TRSRSLSGSNSTLTISNVTRSDAGTYTCV 75

                  ...
gi 2183707411  99 ASN 101
Cdd:pfam13927  76 ASN 78

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

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2183707411  123 PVAVYTWEGNQVNITCEVFAYPSATISWFRDGQLLPSSNySNIKIYNTPSASYLEVTPDSENDFGNYNCTAVNRIGQES 201
Cdd:smart00410   1 PPSVTVKEGESVTLSCEASGSPPPEVTWYKQGGKLLAES-GRFSVSRSGSTSTLTISNVTPEDSGTYTCAATNSSGSAS 78

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 2183707411  37 VTLTCEASGDPIPSITWRTSTRNISSeektlDGHMVVRSHARVSSLTLKSIQYTDAGEYICTASNTIG 104
Cdd:cd00096     1 VTLTCSASGNPPPTITWYKNGKPLPP-----SSRDSRRSELGNGTLTISNVTLEDSGTYTCVASNSAG 63

Immunoglobulin I-set domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411  20 PKITYV-ENQTAMElEEQVTLTCEASGDPIPSITWRTSTRNISSeektlDGHMVVRSHARVSSLTLKSIQYTDAGEYICT 98
Cdd:pfam07679   1 PKFTQKpKDVEVQE-GESARFTCTVTGTPDPEVSWFKDGQPLRS-----SDRFKVTYEGGTYTLTISNVQPDDSGKYTCV 74

                          90
                  ....*....|....*.
gi 2183707411  99 ASNTIGQDSQSMYLEV 114
Cdd:pfam07679  75 ATNSAGEAEASAELTV 90

Immunoglobulin I-set domain;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2183707411 130 EGNQVNITCEVFAYPSATISWFRDGQLLPSSNYsnIKIYNTPSASYLEVTPDSENDFGNYNCTAVNRIGQESLEFIL 206
Cdd:pfam07679  14 EGESARFTCTVTGTPDPEVSWFKDGQPLRSSDR--FKVTYEGGTYTLTISNVQPDDSGKYTCVATNSAGEAEASAEL 88

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 2183707411 134 VNITCEVFAYPSATISWFRDGQLLPSSNYSNIKIYNTPsaSYLEVTPDSENDFGNYNCTAVNRIG 198
Cdd:cd00096     1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELGN--GTLTISNVTLEDSGTYTCVASNSAG 63

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411  27 NQTAMeLEEQVTLTCEASGDPIPSITWRTStrnisseektlDGHMVV-RSHARV-SSLTLKSIQYTDAGEYICTASNTIG 104
Cdd:cd05725     6 NQVVL-VDDSAEFQCEVGGDPVPTVRWRKE-----------DGELPKgRYEILDdHSLKIRKVTAGDMGSYTCVAENMVG 73

                          90
                  ....*....|
gi 2183707411 105 QDSQSMYLEV 114
Cdd:cd05725    74 KIEASATLTV 83

Fibronectin type III domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411 213 SSPSIDQVEP-YSSTAQVQFDEPEaTGGVPILKYKAEWRAVGEEvWHSKWYDAKEASMEgiVTIVGLKPETTYAVRLAAL 291
Cdd:pfam00041   1 SAPSNLTVTDvTSTSLTVSWTPPP-DGNGPITGYEVEYRPKNSG-EPWNEITVPGTTTS--VTLTGLKPGTEYEVRVQAV 76

                  ....*....
gi 2183707411 292 NGKGLGEIS 300
Cdd:pfam00041  77 NGGGEGPPS 85

Fourth 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 fourth 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 2183707411  35 EQVTLTCEASGDPIPSITWRTSTRNISSEEKTLDGHmVVRSHARV-SSLTLKSIQYTDAGEYICTASNTIGQDSQS 109
Cdd:cd20956    17 PSVSLKCVASGNPLPQITWTLDGFPIPESPRFRVGD-YVTSDGDVvSYVNISSVRVEDGGEYTCTATNDVGSVSHS 91

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third 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. This group belongs to the I-set of IgSF domains.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2183707411  35 EQVTLTCEASGDPIPSITWRtstrnisseekTLDGHMVVRSHARVSSLTLK--SIQYTDAGEYICTASNTIGQD 106
Cdd:cd04968    17 QTVTLECFALGNPVPQIKWR-----------KVDGSPSSQWEITTSEPVLEipNVQFEDEGTYECEAENSRGKD 79

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third 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. This group belongs to the I-set of IgSF domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411  33 LEEQVTLTCEASGDPIPSITWRTSTRNI-SSEEKTLDGhmvvrsharvSSLTLKSIQYTDAGEYICTASNTIGQDSQSMY 111
Cdd:cd05851    15 KGQNVTLECFALGNPVPVIRWRKILEPMpATAEISMSG----------AVLKIFNIQPEDEGTYECEAENIKGKDKHQAR 84

                  ....
gi 2183707411 112 LEVQ 115
Cdd:cd05851    85 VYVQ 88

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2183707411  37 VTLTCEASGDPIPSITWRTSTRNISSEEK---TLDGHmvvrsharvssLTLKSIQYTDAGEYICTASNTIGQDSQSMYL 112
Cdd:cd05746     1 VQIPCSAQGDPEPTITWNKDGVQVTESGKfhiSPEGY-----------LAIRDVGVADQGRYECVARNTIGYASVSMVL 68

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 2183707411  20 PKITYVENQTameleeqVTLTCEASGDPIPSITWrtstrnisseEKtlDGHMVVRSH-ARVSS---LTLKSIQ-YTDAGE 94
Cdd:cd20958     8 GNLTAVAGQT-------LRLHCPVAGYPISSITW----------EK--DGRRLPLNHrQRVFPngtLVIENVQrSSDEGE 68

                          90       100
                  ....*....|....*....|.
gi 2183707411  95 YICTASNTIGQ-DSQSMYLEV 114
Cdd:cd20958    69 YTCTARNQQGQsASRSVFVKV 89

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 2183707411  37 VTLTCEASGDPIPSITWRTSTRNISSEeKTLDGHMVVRSharvSSLTLKSIQYTDAGEYICTASNTIGQDSQSMYLEV 114
Cdd:cd20969    20 VQFVCRADGDPPPAILWLSPRKHLVSA-KSNGRLTVFPD----GTLEVRYAQVQDNGTYLCIAANAGGNDSMPAHLHV 92

Immunoglobulin (Ig)-like domain of human titin C terminus and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain from the C-terminus of human titin x and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is gigantic; depending on isoform composition it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone and appears to function similar to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. 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 2183707411 120 LQGPVAVYTWEGNQVNITCEVFAYPSATISWFRDGQLLPSSnySNIKIYNTPSASYLEVTPDSENDFGNYNCTAVNRIGQ 199
Cdd:cd05747     7 LTKPRSLTVSEGESARFSCDVDGEPAPTVTWMREGQIIVSS--QRHQITSTEYKSTFEISKVQMSDEGNYTVVVENSEGK 84

                  ....*..
gi 2183707411 200 ESLEFIL 206
Cdd:cd05747    85 QEAQFTL 91

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        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411  37 VTLTCEASGDPIPSITWRTSTRNisseektldghmvVRSHARVS-----SLTLKSIQYTDAGEYICTASNTIGQDSQSMY 111
Cdd:cd04969    20 VIIECKPKASPKPTISWSKGTEL-------------LTNSSRICilpdgSLKIKNVTKSDEGKYTCFAVNFFGKANSTGS 86

                  ...
gi 2183707411 112 LEV 114
Cdd:cd04969    87 LSV 89

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2183707411  37 VTLTCEASGDPIPSITWRtstrnisSEEKTLDGHMVVRSHARVSSLTLKSIQYTDAGEYICTASNTIGQDSQSMYLEV 114
Cdd:cd05856    22 VRLKCVASGNPRPDITWL-------KDNKPLTPPEIGENKKKKWTLSLKNLKPEDSGKYTCHVSNRAGEINATYKVDV 92

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        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411  16 TAAKPKITYVENQtameleeQVTLTCEASGDPIPSITWRTSTRNISSEEKTldghmvVRSHARVSSLTLKSIQYTDAGEY 95
Cdd:cd20976     5 SSVPKDLEAVEGQ-------DFVAQCSARGKPVPRITWIRNAQPLQYAADR------STCEAGVGELHIQDVLPEDHGTY 71

                          90
                  ....*....|....*....
gi 2183707411  96 ICTASNTIGQDSQSMYLEV 114
Cdd:cd20976    72 TCLAKNAAGQVSCSAWVTV 90

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2183707411  35 EQVTLTCEASGDPIPSITWRTSTRNISSEEKTLdghmvVRSHARVSSLTLKSIQYTDAGEYICTASNTIG 104
Cdd:cd05743     2 ETVEFTCVATGVPTPIINWRLNWGHVPDSARVS-----ITSEGGYGTLTIRDVKESDQGAYTCEAINTRG 66

First immunoglobulin-like domain of vascular endothelial cell adhesion molecule-1 (VCAM-1), and similar domains; member of the I-set of IgSF domains; The members here include the first immunoglobulin-like domain of vascular endothelial cell adhesion molecule-1 (VCAM-1; also known as Cluster of Differentiation 106 (CD106)) and similar proteins. During the inflammation process, these molecules recruit leukocytes onto the vascular endothelium before extravasation to the injured tissues. The interaction of VCAM-1 binding to the beta1 integrin very late antigen (VLA-4) expressed by lymphocytes and monocytes mediates the adhesion of leucocytes to blood vessel walls, and regulates migration across the endothelium. During metastasis, some circulating cancer cells extravasate to a secondary site by a similar process. VCAM-1 may be involved in organ targeted tumor metastasis and may also act as host receptors for viruses and parasites. VCAM-1 contains seven Ig domains. 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 first Ig-like domain of VCAM-1 is a member of the I-set 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, the A strand of the I-set is discontinuous, but lacks a C" strand.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2183707411  26 ENQTAMELEEQVTLTCEASGDPIPSITWRTSTrnisseEKTLDGhmVVRSHARVSSLTLKSIQYTDAGEYICTAS 100
Cdd:cd20943     8 GSRYAAQIGDSVSLTCSTTGCESPSFSWRTQI------DSPLNG--KVRNEGTTSTLTLSPVSFENEHSYLCTVT 74