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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755524377 106 CARDWTFFNGSCYFFSKSQRNWHNSTTACQELGAQLVIIETDEEQTFLQQTSKARGPTWMGLSDMHNEATWHWVDGSPLS 185
Cdd:cd03590    1 CPTNWKSFQSSCYFFSTEKKSWEESRQFCEDMGAHLVIINSQEEQEFISKILSGNRSYWIGLSDEETEGEWKWVDGTPLN 80

                 .
gi 755524377 186 P 186
Cdd:cd03590   81 S 81

C-type lectin-like domain (CTLD) of the type found in human dendritic cell (DC)-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and the related receptor, DC-SIGN receptor (DC-SIGNR); CLECT_DC-SIGN_like: C-type lectin-like domain (CTLD) of the type found in human dendritic cell (DC)-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and the related receptor, DC-SIGN receptor (DC-SIGNR). This group also contains proteins similar to hepatic asialoglycoprotein receptor (ASGP-R) and langerin in human. These proteins are type II membrane proteins with a CTLD ectodomain. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. DC-SIGN is thought to mediate the initial contact between dendritic cells and resting T cells, and may also mediate the rolling of DCs on epithelium. DC-SIGN and DC-SIGNR bind to oligosaccharides present on human tissues, as well as, on pathogens including parasites, bacteria, and viruses. DC-SIGN and DC-SIGNR bind to HIV enhancing viral infection of T cells. DC-SIGN and DC-SIGNR are homotetrameric, and contain four CTLDs stabilized by a coiled coil of alpha helices. The hepatic ASGP-R is an endocytic recycling receptor which binds and internalizes desialylated glycoproteins having a terminal galactose or N-acetylgalactosamine residues on their N-linked carbohydrate chains, via the clathrin-coated pit mediated endocytic pathway, and delivers them to lysosomes for degradation. It has been proposed that glycoproteins bearing terminal Sia (sialic acid) alpha2, 6GalNAc and Sia alpha2, 6Gal are endogenous ligands for ASGP-R and that ASGP-R participates in regulating the relative concentration of serum glycoproteins bearing alpha 2,6-linked Sia. The human ASGP-R is a hetero-oligomer composed of two subunits, both of which are found within this group. Langerin is expressed in a subset of dendritic leukocytes, the Langerhans cells (LC). Langerin induces the formation of Birbeck Granules (BGs) and associates with these BGs following internalization. Langerin binds, in a calcium-dependent manner, to glyco-conjugates containing mannose and related sugars mediating their uptake and degradation. Langerin molecules oligomerize as trimers with three CTLDs held together by a coiled-coil of alpha helices.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755524377 106 CARDWTFFNGSCYFFSKSQRNWHNSTTACQELGAQLVIIETDEEQTFLQQTSKARGPTWMGLSDMHNEATWHWVDGSPLS 185
Cdd:cd03590    1 CPTNWKSFQSSCYFFSTEKKSWEESRQFCEDMGAHLVIINSQEEQEFISKILSGNRSYWIGLSDEETEGEWKWVDGTPLN 80

                 .
gi 755524377 186 P 186
Cdd:cd03590   81 S 81

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 755524377  124 QRNWHNSTTACQELGAQLVIIETDEEQTFLQQTSKARG-PTWMGLSDMHNEATWHWVDGSPLS 185
Cdd:pfam00059   1 SKTWDEAREACRKLGGHLVSINSAEELDFLSSTLKKSNkYFWIGLTDRKNEGTWKWVDGSPVN 63

C-type lectin-like domain (CTLD) of the type found in human dendritic cell (DC)-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and the related receptor, DC-SIGN receptor (DC-SIGNR); CLECT_DC-SIGN_like: C-type lectin-like domain (CTLD) of the type found in human dendritic cell (DC)-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and the related receptor, DC-SIGN receptor (DC-SIGNR). This group also contains proteins similar to hepatic asialoglycoprotein receptor (ASGP-R) and langerin in human. These proteins are type II membrane proteins with a CTLD ectodomain. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. DC-SIGN is thought to mediate the initial contact between dendritic cells and resting T cells, and may also mediate the rolling of DCs on epithelium. DC-SIGN and DC-SIGNR bind to oligosaccharides present on human tissues, as well as, on pathogens including parasites, bacteria, and viruses. DC-SIGN and DC-SIGNR bind to HIV enhancing viral infection of T cells. DC-SIGN and DC-SIGNR are homotetrameric, and contain four CTLDs stabilized by a coiled coil of alpha helices. The hepatic ASGP-R is an endocytic recycling receptor which binds and internalizes desialylated glycoproteins having a terminal galactose or N-acetylgalactosamine residues on their N-linked carbohydrate chains, via the clathrin-coated pit mediated endocytic pathway, and delivers them to lysosomes for degradation. It has been proposed that glycoproteins bearing terminal Sia (sialic acid) alpha2, 6GalNAc and Sia alpha2, 6Gal are endogenous ligands for ASGP-R and that ASGP-R participates in regulating the relative concentration of serum glycoproteins bearing alpha 2,6-linked Sia. The human ASGP-R is a hetero-oligomer composed of two subunits, both of which are found within this group. Langerin is expressed in a subset of dendritic leukocytes, the Langerhans cells (LC). Langerin induces the formation of Birbeck Granules (BGs) and associates with these BGs following internalization. Langerin binds, in a calcium-dependent manner, to glyco-conjugates containing mannose and related sugars mediating their uptake and degradation. Langerin molecules oligomerize as trimers with three CTLDs held together by a coiled-coil of alpha helices.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755524377 106 CARDWTFFNGSCYFFSKSQRNWHNSTTACQELGAQLVIIETDEEQTFLQQTSKARGPTWMGLSDMHNEATWHWVDGSPLS 185
Cdd:cd03590    1 CPTNWKSFQSSCYFFSTEKKSWEESRQFCEDMGAHLVIINSQEEQEFISKILSGNRSYWIGLSDEETEGEWKWVDGTPLN 80

                 .
gi 755524377 186 P 186
Cdd:cd03590   81 S 81

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 755524377 116 SCYFFSKSQRNWHNSTTACQELGAQLVIIETDEEQTFLQQTSKARGPT--WMGLSDMHNEATWHWVDGSPLS 185
Cdd:cd00037    1 SCYKFSTEKLTWEEAQEYCRSLGGHLASIHSEEENDFLASLLKKSSSSdvWIGLNDLSSEGTWKWSDGSPLV 72

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 755524377  124 QRNWHNSTTACQELGAQLVIIETDEEQTFLQQTSKARG-PTWMGLSDMHNEATWHWVDGSPLS 185
Cdd:pfam00059   1 SKTWDEAREACRKLGGHLVSINSAEELDFLSSTLKKSNkYFWIGLTDRKNEGTWKWVDGSPVN 63

C-type lectin-like protein; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755524377  91 LMQLKAEVHDGLCQ--PCARDWTFFNGSCYFFSKSQRNWHNSTTACQELGAQLVIIETDEEQTFLQQTsKARGPTWMGLS 168
Cdd:PHA02642  71 LMAFKSDTQEPTIKyvTCPKGWIGFGYKCFYFSEDSKNWTFGNTFCTSLGATLVKVETEEELNFLKRY-KDSSDHWIGLN 149

                         90
                 ....*....|....
gi 755524377 169 DMHNEATWHWVDGS 182
Cdd:PHA02642 150 RESSNHPWKWADNS 163

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755524377 106 CARDWTFFNGSCYFFSKSQRNWHNSTTACQEL--GAQLVIIETDEEQTFL----QQTSKARGPTWMGLSDMHNEATWHWV 179
Cdd:cd03594    1 CPKGWLPYKGNCYGYFRQPLSWSDAELFCQKYgpGAHLASIHSPAEAAAIasliSSYQKAYQPVWIGLHDPQQSRGWEWS 80

                 ...
gi 755524377 180 DGS 182
Cdd:cd03594   81 DGS 83

C-type lectin-like domain (CTLD) of the type found in the tetranectin (TN), cartilage derived C-type lectin (CLECSF1), and stem cell growth factor (SCGF); CLECT_tetranectin_like: C-type lectin-like domain (CTLD) of the type found in the tetranectin (TN), cartilage derived C-type lectin (CLECSF1), and stem cell growth factor (SCGF). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. TN binds to plasminogen and stimulates activation of plasminogen, playing a key role in the regulation of proteolytic processes. The TN CTLD binds two calcium ions. Its calcium free form binds to various kringle-like protein ligands. Two residues involved in the coordination of calcium are critical for the binding of TN to the fourth kringle (K4) domain of plasminogen (Plg K4). TN binds the kringle 1-4 form of angiostatin (AST K1-4). AST K1-4 is a fragment of Plg, commonly found in cancer tissues. TN inhibits the binding of Plg and AST K1-4 to the extracellular matrix (EMC) of endothelial cells and counteracts the antiproliferative effects of AST K1-4 on these cells. TN also binds the tenth kringle domain of apolipoprotein (a). In addition, TN binds fibrin and complex polysaccharides in a Ca2+ dependent manner. The binding site for complex sulfated polysaccharides is N-terminal to the CTLD. TN is homotrimeric; N-terminal to the CTLD is an alpha helical domain responsible for trimerization of monomeric units. TN may modulate angiogenesis through interactions with angiostatin and coagulation through interaction with fibrin. TN may play a role in myogenesis and in bone development. Mice having a deletion in the TN gene exhibit a kyphotic spine abnormality. TN is a useful prognostic marker of certain cancer types. CLECSF1 is expressed in cartilage tissue, which is primarily intracellular matrix (ECM), and is a candidate for organizing ECM. SCGF is strongly expressed in bone marrow and is a cytokine for primitive hematopoietic progenitor cells.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 755524377 117 CYFFSKSQRNWHNSTTACQELGAQLVIIETDEE----QTFLQQTSKARGPTWMGLSDMHNEATWHWVDGSPLSPRHIHR 191
Cdd:cd03596   11 CYLVSEETKHYHEASEDCIARGGTLATPRDSDEndalRDYVKASVPGNWEVWLGINDMVAEGKWVDVNGSPISYFNWER 89

C-type lectin-like domain (CTLD) of the type found in the human type-1A transmembrane proteins chondrolectin (CHODL) and layilin; CLECT_chondrolectin_like: C-type lectin-like domain (CTLD) of the type found in the human type-1A transmembrane proteins chondrolectin (CHODL) and layilin. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. CHODL is predominantly expressed in muscle cells and is associated with T-cell maturation. Various alternatively spliced isoforms have been of CHODL have been identified. The transmembrane form of CHODL is localized in the ER-Golgi apparatus. Layilin is widely expressed in different cell types. The extracellular CTLD of layilin binds hyaluronan (HA), a major constituent of the extracellular matrix (ECM). The cytoplasmic tail of layilin binds various members of the band 4.1/ERM superfamily (talin, radixin, and merlin). The ERM proteins are cytoskeleton-membrane linker molecules which link actin to receptors in the plasma membrane. Layilin co-localizes in with talin in membrane ruffles and may mediate signals from the ECM to the cell cytoskeleton.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755524377 113 FNGSCY---FFSKSQR--NWHNSTTACQELGAQLVIIETDEEQ----TFLQQTSKARGPTWMGL---SDMHNEAT----- 175
Cdd:cd03595    8 TEKPCYkiaYFQDSRRrlNFEEARQACREDGGELLSIESENEQklieRFIQTLRASDGDFWIGLrrsSQYNVTSSacssl 87

                         90
                 ....*....|....*
gi 755524377 176 WHWVDGSPLSPRHIH 190
Cdd:cd03595   88 YYWLDGSISTFRNWY 102

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 755524377 118 YFFSKSQRNWHNSTTACQELGAQLVIIETDEEQTFLQQTSKARGPT--WMGLSDMHNEatWHWVD 180
Cdd:cd03592    3 YHYSTEKMTFNEAVKYCKSRGTDLVAIQNAEENALLNGFALKYNLGyyWIDGNDINNE--GTWVD 65

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755524377 106 CARDWTFFNGSCYFFSKSQRNWHNSTTACQELGAQLVIIETDEEQTFL-------QQTSKARGPtWMGLSDMhNEATWHW 178
Cdd:cd03597    1 CGEGWHLVGNSCLKINTARESYDNAKLYCRNLNAVLASLTTQKKVEFVlkelqkhQMTKQKLTP-WVGLRKI-NVSYWCW 78

                 ....*..
gi 755524377 179 VDGSPLS 185
Cdd:cd03597   79 EDMSPFT 85