C-type lectin (CTL)/C-type lectin-like (CTLD) domain; CLECT: C-type lectin (CTL)/C-type lectin-like (CTLD) domain; protein domains homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. This group is chiefly comprised of eukaryotic CTLDs, but contains some, as yet functionally uncharacterized, bacterial CTLDs. Many CTLDs are calcium-dependent carbohydrate binding modules; other CTLDs bind protein ligands, lipids, and inorganic surfaces, including CaCO3 and ice. Animal C-type lectins are involved in such functions as extracellular matrix organization, endocytosis, complement activation, pathogen recognition, and cell-cell interactions. For example: mannose-binding lectin and lung surfactant proteins A and D bind carbohydrates on surfaces (e.g. pathogens, allergens, necrotic, and apoptotic cells) and mediate functions associated with killing and phagocytosis; P (platlet)-, E (endothelial)-, and L (leukocyte)- selectins (sels) mediate the initial attachment, tethering, and rolling of lymphocytes on inflamed vascular walls enabling subsequent lymphocyte adhesion and transmigration. CTLDs may bind a variety of carbohydrate ligands including mannose, N-acetylglucosamine, galactose, N-acetylgalactosamine, and fucose. Several CTLDs bind to protein ligands, and only some of these binding interactions are Ca2+-dependent; including the CTLDs of Coagulation Factors IX/X (IX/X) and Von Willebrand Factor (VWF) binding proteins, and natural killer cell receptors. C-type lectins, such as lithostathine, and some type II antifreeze glycoproteins function in a Ca2+-independent manner to bind inorganic surfaces. Many proteins in this group contain a single CTLD; these CTLDs associate with each other through several different surfaces to form dimers, trimers, or tetramers, from which ligand-binding sites project in different orientations. Various vertebrate type 1 transmembrane proteins including macrophage mannose receptor, endo180, phospholipase A2 receptor, and dendritic and epithelial cell receptor (DEC205) have extracellular domains containing 8 or more CTLDs; these CTLDs remain in the parent model. In some members (IX/X and VWF binding proteins), a loop extends to the adjoining domain to form a loop-swapped dimer. A similar conformation is seen in the macrophage mannose receptor CRD4's putative non-sugar bound form of the domain in the acid environment of the endosome. Lineage specific expansions of CTLDs have occurred in several animal lineages including Drosophila melanogaster and Caenorhabditis elegans; these CTLDs also remain in the parent model.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A       14 CPEGTNAYRSYCY-YFNEDReTWVDADLYCQNM-NSGNLVSVLTQAEGAFVASLIKESGTDDFNVWIGLHDPKKNRAWHW 91
Cdd:cd03594   1 CPKGWLPYKGNCYgYFRQPL-SWSDAELFCQKYgPGAHLASIHSPAEAAAIASLISSYQKAYQPVWIGLHDPQQSRGWEW 79

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|.
1QDD_A       92 SSGSLVSYKSWGIGAPSSvNPGYCVSLTSSTGFQKWKDVPCEDKFSFVCKF 142
Cdd:cd03594  80 SDGSKLDYRSWDRNPPYA-RGGYCAELSRSTGFLKWNDANCEERNPFICKY 129

C-type lectin-like domain (CTLD) of the type found in Human REG-1 (lithostathine), REG-4, and avian eggshell-specific proteins: ansocalcin, structhiocalcin-1(SCA-1), and -2(SCA-2); CLECT_REG-1_like: C-type lectin-like domain (CTLD) of the type found in Human REG-1 (lithostathine), REG-4, and avian eggshell-specific proteins: ansocalcin, structhiocalcin-1(SCA-1), and -2(SCA-2). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. REG-1 is a proliferating factor which participates in various kinds of tissue regeneration including pancreatic beta-cell regeneration, regeneration of intestinal mucosa, regeneration of motor neurons, and perhaps in tissue regeneration of damaged heart. REG-1 may play a role on the pathophysiology of Alzheimer's disease and in the development of gastric cancers. Its expression is correlated with reduced survival from early-stage colorectal cancer. REG-1 also binds and aggregates several bacterial strains from the intestinal flora and it has been suggested that it is involved in the control of the intestinal bacterial ecosystem. Rat lithostathine has calcium carbonate crystal inhibitor activity in vitro. REG-IV is unregulated in pancreatic, gastric, hepatocellular, and prostrate adenocarcinomas. REG-IV activates the EGF receptor/Akt/AP-1 signaling pathway in colorectal carcinoma. Ansocalcin, SCA-1 and -2 are found at high concentration in the calcified egg shell layer of goose and ostrich, respectively and tend to form aggregates. Ansocalcin nucleates calcite crystal aggregates in vitro.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A       14 CPEGTNAYRSYCY-YFNEDReTWVDADLYCQNM-NSGNLVSVLTQAEGAFVASLIKESGTDDFNVWIGLHDPKKNRAWHW 91
Cdd:cd03594   1 CPKGWLPYKGNCYgYFRQPL-SWSDAELFCQKYgPGAHLASIHSPAEAAAIASLISSYQKAYQPVWIGLHDPQQSRGWEW 79

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|.
1QDD_A       92 SSGSLVSYKSWGIGAPSSvNPGYCVSLTSSTGFQKWKDVPCEDKFSFVCKF 142
Cdd:cd03594  80 SDGSKLDYRSWDRNPPYA-RGGYCAELSRSTGFLKWNDANCEERNPFICKY 129

Lectin C-type domain; This family includes both long and short form C-type

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A         32 RETWVDADLYCQNMNsGNLVSVLTQAEGAFVASLIKESGTDdfnVWIGLHDPKKNRAWHWSSGSLVSYKSWGIGAPSSVN 111
Cdd:pfam00059   1 SKTWDEAREACRKLG-GHLVSINSAEELDFLSSTLKKSNKY---FWIGLTDRKNEGTWKWVDGSPVNYTNWAPEPNNNGE 76

                          90       100       110
                  ....*....|....*....|....*....|.
1QDD_A        112 PGYCVSLTSSTGfqKWKDVPCEDKFSFVCKF 142
Cdd:pfam00059  77 NEDCVELSSSSG--KWNDENCNSKNPFVCEK 105

polycystin cation channel protein; The Polycystin Cation Channel (PCC) Family (TC 1.A.5) Polycystin is a huge protein of 4303aas. Its repeated leucine-rich (LRR) segment is found in many proteins. It contains 16 polycystic kidney disease (PKD) domains, one LDL-receptor class A domain, one C-type lectin family domain, and 16-18 putative TMSs in positions between residues 2200 and 4100. Polycystin-L has been shown to be a cation (Na+, K+ and Ca2+) channel that is activated by Ca2+. Two members of the PCC family (polycystin 1 and 2) are mutated in autosomal dominant polycystic kidney disease, and polycystin-L is deleted in mice with renal and retinal defects. Note: this model is restricted to the amino half.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A          14 CPEGTNAY--RSYCYYFNEDRETWVDADLYCQNMNSGNLVSVLTQAEGAFVASLIKESGtdDFNVWIGLHDPK--KNRAW 89
Cdd:TIGR00864  318 CPKDGEIFeeNGHCFQIVPEEAAWLDAQEQCLARAGAALAIVDNDALQNFLARKVTHSL--DRGVWIGFSDVNgaEKGPA 395

                           90       100       110       120       130
                   ....*....|....*....|....*....|....*....|....*....|....*.
1QDD_A          90 HWSSG-SLVSYKSWGIGAPSSVNPGYCVSLtsstGFQKWKDV-PCEDKFSFVCKFK 143
Cdd:TIGR00864  396 HQGEAfEAEECEEGLAGEPHPARAEHCVRL----DPRGQCNSdLCNAPHAYVCELN 447

C-type lectin-like domain (CTLD) of the type found in Human REG-1 (lithostathine), REG-4, and avian eggshell-specific proteins: ansocalcin, structhiocalcin-1(SCA-1), and -2(SCA-2); CLECT_REG-1_like: C-type lectin-like domain (CTLD) of the type found in Human REG-1 (lithostathine), REG-4, and avian eggshell-specific proteins: ansocalcin, structhiocalcin-1(SCA-1), and -2(SCA-2). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. REG-1 is a proliferating factor which participates in various kinds of tissue regeneration including pancreatic beta-cell regeneration, regeneration of intestinal mucosa, regeneration of motor neurons, and perhaps in tissue regeneration of damaged heart. REG-1 may play a role on the pathophysiology of Alzheimer's disease and in the development of gastric cancers. Its expression is correlated with reduced survival from early-stage colorectal cancer. REG-1 also binds and aggregates several bacterial strains from the intestinal flora and it has been suggested that it is involved in the control of the intestinal bacterial ecosystem. Rat lithostathine has calcium carbonate crystal inhibitor activity in vitro. REG-IV is unregulated in pancreatic, gastric, hepatocellular, and prostrate adenocarcinomas. REG-IV activates the EGF receptor/Akt/AP-1 signaling pathway in colorectal carcinoma. Ansocalcin, SCA-1 and -2 are found at high concentration in the calcified egg shell layer of goose and ostrich, respectively and tend to form aggregates. Ansocalcin nucleates calcite crystal aggregates in vitro.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A       14 CPEGTNAYRSYCY-YFNEDReTWVDADLYCQNM-NSGNLVSVLTQAEGAFVASLIKESGTDDFNVWIGLHDPKKNRAWHW 91
Cdd:cd03594   1 CPKGWLPYKGNCYgYFRQPL-SWSDAELFCQKYgPGAHLASIHSPAEAAAIASLISSYQKAYQPVWIGLHDPQQSRGWEW 79

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|.
1QDD_A       92 SSGSLVSYKSWGIGAPSSvNPGYCVSLTSSTGFQKWKDVPCEDKFSFVCKF 142
Cdd:cd03594  80 SDGSKLDYRSWDRNPPYA-RGGYCAELSRSTGFLKWNDANCEERNPFICKY 129

C-type lectin (CTL)/C-type lectin-like (CTLD) domain; CLECT: C-type lectin (CTL)/C-type lectin-like (CTLD) domain; protein domains homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. This group is chiefly comprised of eukaryotic CTLDs, but contains some, as yet functionally uncharacterized, bacterial CTLDs. Many CTLDs are calcium-dependent carbohydrate binding modules; other CTLDs bind protein ligands, lipids, and inorganic surfaces, including CaCO3 and ice. Animal C-type lectins are involved in such functions as extracellular matrix organization, endocytosis, complement activation, pathogen recognition, and cell-cell interactions. For example: mannose-binding lectin and lung surfactant proteins A and D bind carbohydrates on surfaces (e.g. pathogens, allergens, necrotic, and apoptotic cells) and mediate functions associated with killing and phagocytosis; P (platlet)-, E (endothelial)-, and L (leukocyte)- selectins (sels) mediate the initial attachment, tethering, and rolling of lymphocytes on inflamed vascular walls enabling subsequent lymphocyte adhesion and transmigration. CTLDs may bind a variety of carbohydrate ligands including mannose, N-acetylglucosamine, galactose, N-acetylgalactosamine, and fucose. Several CTLDs bind to protein ligands, and only some of these binding interactions are Ca2+-dependent; including the CTLDs of Coagulation Factors IX/X (IX/X) and Von Willebrand Factor (VWF) binding proteins, and natural killer cell receptors. C-type lectins, such as lithostathine, and some type II antifreeze glycoproteins function in a Ca2+-independent manner to bind inorganic surfaces. Many proteins in this group contain a single CTLD; these CTLDs associate with each other through several different surfaces to form dimers, trimers, or tetramers, from which ligand-binding sites project in different orientations. Various vertebrate type 1 transmembrane proteins including macrophage mannose receptor, endo180, phospholipase A2 receptor, and dendritic and epithelial cell receptor (DEC205) have extracellular domains containing 8 or more CTLDs; these CTLDs remain in the parent model. In some members (IX/X and VWF binding proteins), a loop extends to the adjoining domain to form a loop-swapped dimer. A similar conformation is seen in the macrophage mannose receptor CRD4's putative non-sugar bound form of the domain in the acid environment of the endosome. Lineage specific expansions of CTLDs have occurred in several animal lineages including Drosophila melanogaster and Caenorhabditis elegans; these CTLDs also remain in the parent model.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A       24 YCYYFNEDRETWVDADLYCQNMNsGNLVSVLTQAEGAFVASLIKESGTDDFnvWIGLHDPKKNRAWHWSSGS-LVSYKSW 102
Cdd:cd00037   1 SCYKFSTEKLTWEEAQEYCRSLG-GHLASIHSEEENDFLASLLKKSSSSDV--WIGLNDLSSEGTWKWSDGSpLVDYTNW 77

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
1QDD_A      103 GIGAPSSVNPGYCVSLTSSTGFqKWKDVPCEDKFSFVCKF 142
Cdd:cd00037  78 APGEPNPGGSEDCVVLSSSSDG-KWNDVSCSSKLPFICEK 116

Lectin C-type domain; This family includes both long and short form C-type

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A         32 RETWVDADLYCQNMNsGNLVSVLTQAEGAFVASLIKESGTDdfnVWIGLHDPKKNRAWHWSSGSLVSYKSWGIGAPSSVN 111
Cdd:pfam00059   1 SKTWDEAREACRKLG-GHLVSINSAEELDFLSSTLKKSNKY---FWIGLTDRKNEGTWKWVDGSPVNYTNWAPEPNNNGE 76

                          90       100       110
                  ....*....|....*....|....*....|.
1QDD_A        112 PGYCVSLTSSTGfqKWKDVPCEDKFSFVCKF 142
Cdd:pfam00059  77 NEDCVELSSSSG--KWNDENCNSKNPFVCEK 105

C-type lectin-like domain (CTLD) of the type found in chondroitin sulfate proteoglycan core proteins; CLECT_CSPGs: C-type lectin-like domain (CTLD) of the type found in chondroitin sulfate proteoglycan core proteins (CSPGs) in human and chicken aggrecan, frog brevican, and zebra fish dermacan. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. In cartilage, aggrecan forms cartilage link protein stabilized aggregates with hyaluronan (HA). These aggregates contribute to the tissue's load bearing properties. Aggregates having other CSPGs substituting for aggrecan may contribute to the structural integrity of many different tissues. Xenopus brevican is expressed in the notochord and the brain during early embryogenesis. Zebra fish dermacan is expressed in dermal bones and may play a role in dermal bone development. CSPGs do contain LINK domain(s) which bind HA. These LINK domains are considered by one classification system to be a variety of CTLD, but are omitted from this hierarchical classification based on insignificant sequence similarity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A       14 CPEGTNAYRSYCYYFNEDRETWVDADLYCQnMNSGNLVSVLTQAEGAFVASLikesgTDDFNvWIGLHDPKKNRAWHWSS 93
Cdd:cd03588   1 CEEGWDKFQGHCYRHFPDRETWEDAERRCR-EQQGHLSSIVTPEEQEFVNNN-----AQDYQ-WIGLNDRTIEGDFRWSD 73

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|.
1QDD_A       94 GSLVSYKSWGIGAPSS---VNPGYCVSLTSSTGfqKWKDVPCEDKFSFVCK 141
Cdd:cd03588  74 GHPLQFENWRPNQPDNffaTGEDCVVMIWHEEG--EWNDVPCNYHLPFTCK 122

A bacterial subgroup of the C-type lectin-like (CTLD) domain; a subgroup of bacterial protein domains homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins; CLECT_VCBS: A bacterial subgroup of the C-type lectin-like (CTLD) domain; a subgroup of bacterial protein domains homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. Many CTLDs are calcium-dependent carbohydrate binding modules; other CTLDs bind protein ligands, lipids, and inorganic surfaces including CaCO3 and ice. Bacterial CTLDs within this group are functionally uncharacterized. Animal C-type lectins are involved in such functions as extracellular matrix organization, endocytosis, complement activation, pathogen recognition, and cell-cell interactions. CTLDs may bind a variety of carbohydrate ligands including mannose, N-acetylglucosamine, galactose, N-acetylgalactosamine, and fucose. CTLDs associate with each other through several different surfaces to form dimers, trimers, or tetramers from which ligand-binding sites project in different orientations. In some CTLDs a loop extends to the adjoining domain to form a loop-swapped dimer.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A       26 YYFNEDRETWVDADLYCQNMnSGNLVSVLTQAEGAFVASLIKESGtddfNVWIGLHDPKKNRAWHWSSGSLVSYKSWGIG 105
Cdd:cd03603   3 YKFVDGGMTWEAAQTLAESL-GGHLVTINSAEENDWLLSNFGGYG----ASWIGASDAATEGTWKWSDGEESTYTNWGSG 77

                ....*....
1QDD_A      106 APSSVNPGY 114
Cdd:cd03603  78 EPHNNGGGN 86

C-type lectin-like domain (CTLD) of the type found in human collectins including lung surfactant proteins A and D, mannose- or mannan binding lectin (MBL), and CL-L1 (collectin liver 1); CLECT_collectin_like: C-type lectin-like domain (CTLD) of the type found in human collectins including lung surfactant proteins A and D, mannose- or mannan binding lectin (MBL), and CL-L1 (collectin liver 1). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. The CTLDs of these collectins bind carbohydrates on surfaces (e.g. pathogens, allergens, necrotic, or apoptotic cells) and mediate functions associated with killing and phagocytosis. MBPs recognize high mannose oligosaccharides in a calcium dependent manner, bind to a broad range of pathogens, and trigger cell killing by activating the complement pathway. MBP also acts directly as an opsonin. SP-A and SP-D in addition to functioning as host defense components, are components of pulmonary surfactant which play a role in surfactant homeostasis. Pulmonary surfactant is a phospholipid-protein complex which reduces the surface tension within the lungs. SP-A binds the major surfactant lipid: dipalmitoylphosphatidylcholine (DPPC). SP-D binds two minor components of surfactant that contain sugar moieties: glucosylceramide and phosphatidylinositol (PI). MBP and SP-A, -D monomers are homotrimers with an N-terminal collagen region and three CTLDs. Multiple homotrimeric units associate to form supramolecular complexes. MBL deficiency results in an increased susceptibility to a large number of different infections and to inflammatory disease, such as rheumatoid arthritis.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A       26 YYFNEDRETWVDADLYCQNmNSGNLVSVLTQAEGAFVASLIKESGTddfNVWIGLHDPKKNRAWHWSSGSLVSYKSWGIG 105
Cdd:cd03591   4 FVTNGEEKNFDDAQKLCSE-AGGTLAMPRNAAENAAIASYVKKGNT---YAFIGITDLETEGQFVYLDGGPLTYTNWKPG 79

                        90       100       110
                ....*....|....*....|....*....|....*...
1QDD_A      106 APSSVNPGY-CVSLTSSTgfqKWKDVPCEDKFSFVCKF 142
Cdd:cd03591  80 EPNNAGGGEdCVEMYTSG---KWNDVACNLTRLFVCEF 114

C-type lectin-like domain (CTLD) of the type found in human thrombomodulin(TM), Endosialin, C14orf27, and C1qR; CLECT_thrombomodulin_like: C-type lectin-like domain (CTLD) of the type found in human thrombomodulin(TM), Endosialin, C14orf27, and C1qR. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. In these thrombomodulin-like proteins the residues involved in coordinating Ca2+ in the classical MBP-A CTLD are not conserved. TM exerts anti-fibrinolytic and anti-inflammatory activity. TM also regulates blood coagulation in the anticoagulant protein C pathway. In this pathway, the procoagulant properties of thrombin (T) are lost when it binds TM. TM also plays a key role in tumor biology. It is expressed on endothelial cells and on several type of tumor cell including squamous cell carcinoma. Loss of TM expression correlates with advanced stage and poor prognosis. Loss of function of TM function may be associated with arterial or venous thrombosis and with late fetal loss. Soluble molecules of TM retaining the CTLD are detected in human plasma and urine where higher levels indicate injury and/or enhanced turnover of the endothelium. C1qR is expressed on endothelial cells and stem cells. It is also expressed on monocots and neutrophils, where it is subject to ectodomain shedding. Soluble forms of C1qR retaining the CTLD is detected in human plasma. C1qR modulates the phagocytosis of apoptotic cells in vivo. C1qR-deficient mice are defective in clearance of apoptotic cells in vivo. The cytoplasmic tail of C1qR, C-terminal to the CTLD of CD93, contains a PDZ binding domain which interacts with the PDZ domain-containing adaptor protein, GIPC. The juxtamembrane region of this tail interacts with the ezrin/radixin/moesin family. Endosialin functions in the growth and progression of abdominal tumors and is expressed in the stroma of several tumors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A       25 CYYFNEDRETWVDADLYCQNmNSGNLVSVLTQAE----GAFVASLIKESGTDDFNVWIGLHDPKKN--------RAWHW- 91
Cdd:cd03600   6 CYTLHPQKLTFLEAQRSCIE-LGGNLATVRSGEEadvvSLLLAAGPGRHGRGSLRLWIGLQREPRQcsdpslplRGFSWv 84

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|....*
1QDD_A       92 SSGSLVSYKSWGIGAPSSVNPGYCVSLTSSTGFQ---KWKDVPCEDKFS-FVCKF 142
Cdd:cd03600  85 TGDQDTDFSNWLQEPAGTCTSPRCVALSAAGSTPdnlKWKDGPCSARADgYLCKF 139

C-type lectin-like protein; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A         2 EAQTELPQAR-ISCPEGTNAYRSYCYYFNEDRETWVDADLYCQNMNSgNLVSVLTQAEGAFVASLikesgTDDFNVWIGL 80
Cdd:PHA02642  75 KSDTQEPTIKyVTCPKGWIGFGYKCFYFSEDSKNWTFGNTFCTSLGA-TLVKVETEEELNFLKRY-----KDSSDHWIGL 148

                         90
                 ....*....|....*
1QDD_A        81 HDPKKNRAWHWSSGS 95
Cdd:PHA02642 149 NRESSNHPWKWADNS 163

C-type lectin-like domain (CTLD) of the type found in the type 1 transmembrane proteins: P(platlet)-, E(endothelial)-, and L(leukocyte)- selectins (sels); CLECT_selectins_like: C-type lectin-like domain (CTLD) of the type found in the type 1 transmembrane proteins: P(platlet)-, E(endothelial)-, and L(leukocyte)- selectins (sels). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. P- E- and L-sels are cell adhesion receptors that mediate the initial attachment, tethering, and rolling of lymphocytes on inflamed vascular walls enabling subsequent lymphocyte adhesion and transmigration. L- sel is expressed constitutively on most leukocytes. P-sel is stored in the Weibel-Palade bodies of endothelial cells and in the alpha granules of platlets. E- sels are present on endothelial cells. Following platelet and/or endothelial cell activation P- sel is rapidly translocated to the cell surface and E-sel expression is induced. The initial step in leukocyte migration involves interactions of selectins with fucosylated, sialylated, and sulfated carbohydrate moieties on target ligands displayed on glycoprotein scaffolds on endothelial cells and leucocytes. A major ligand of P- E- and L-sels is PSGL-1 (P-sel glycoprotein ligand). Interactions of E- and P- sels with tumor cells may promote extravasation of cancer cells. Regulation of L-sel and P-sel function includes proteolytic shedding of the most extracellular portion (containing the CTLD) from the cell surface. Increased levels of the soluble form of P-sel in the plasma have been found in a number of diseases including coronary disease and diabetes. E- and P- sel also play roles in the development of synovial inflammation in inflammatory arthritis. Platelet P-sel, but not endothelial P-sel, plays a role in the inflammatory response and neointimal formation after arterial injury. Selectins may also function as signal-transducing receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A       26 YYFNEDRETWVDADLYCQNMNSgNLVSVLTQAEGAFVASLIKESGTDDFnvWIGLHDPKKNRAWHWSSGSLVSYKSWGIG 105
Cdd:cd03592   3 YHYSTEKMTFNEAVKYCKSRGT-DLVAIQNAEENALLNGFALKYNLGYY--WIDGNDINNEGTWVDTDKKELEYKNWAPG 79

                        90       100       110
                ....*....|....*....|....*....|....*.
1QDD_A      106 APSSVNPGYCV-SLTSSTGfqKWKDVPCEDKFSFVC 140
Cdd:cd03592  80 EPNNGRNENCLeIYIKDNG--KWNDEPCSKKKSAIC 113

C-type lectin-like domain (CTLD) of the type found in human and mouse attractin (AtrN) and attractin-like protein (ALP); CLECT_attractin_like: C-type lectin-like domain (CTLD) of the type found in human and mouse attractin (AtrN) and attractin-like protein (ALP). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. Mouse AtrN (the product of the mahogany gene) has been shown to bind Agouti protein and to function in agouti-induced pigmentation and obesity. Mutations in AtrN have also been shown to cause spongiform encephalopathy and hypomyelination in rats and hamsters. The cytoplasmic region of mouse ALP has been shown to binds to melanocortin receptor (MCR4). Signaling through MCR4 plays a role in appetite suppression. Attractin may have therapeutic potential in the treatment of obesity. Human attractin (hAtrN) has been shown to be expressed on activated T cells and released extracellularly. The circulating serum attractin induces the spreading of monocytes that become the focus of the clustering of non-proliferating T cells.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1QDD_A       14 CPEGTNAYRSYCYYFNEDRETWVDADLYCQNMNsGNLVSVLTQAEGAFVASLIKESGTDDFNV--WIGLHdpKKNRA-WH 90
Cdd:cd03597   1 CGEGWHLVGNSCLKINTARESYDNAKLYCRNLN-AVLASLTTQKKVEFVLKELQKHQMTKQKLtpWVGLR--KINVSyWC 77

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....
1QDD_A       91 WSSGSLVSYKS--WGIGAPSsvNPGYCVSLTSSTgFQKWKDVPC 132
Cdd:cd03597  78 WEDMSPFTNTTlqWLPGEPS--DAGFCGYLEEPA-VSGLKANPC 118