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.

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gi 1622842139  83 CPPNWIIYEKSCYLFSPSLNSWDGSKRQCSQLGSNLIKIDSSKEL 127
Cdd:cd03593     1 CPKDWICYGNKCYYFSMEKKTWNESKEACSSKNSSLLKIDDEEEL 45

C-type lectin-like domain (CTLD) of the type found in natural killer cell receptors (NKRs); CLECT_NK_receptors_like: C-type lectin-like domain (CTLD) of the type found in natural killer cell receptors (NKRs), including proteins similar to oxidized low density lipoprotein (OxLDL) receptor (LOX-1), CD94, CD69, NKG2-A and -D, osteoclast inhibitory lectin (OCIL), dendritic cell-associated C-type lectin-1 (dectin-1), human myeloid inhibitory C-type lectin-like receptor (MICL), mast cell-associated functional antigen (MAFA), killer cell lectin-like receptors: subfamily F, member 1 (KLRF1) and subfamily B, member 1 (KLRB1), and lys49 receptors. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. NKRs are variously associated with activation or inhibition of natural killer (NK) cells. Activating NKRs stimulate cytolysis by NK cells of virally infected or transformed cells; inhibitory NKRs block cytolysis upon recognition of markers of healthy self cells. Most Lys49 receptors are inhibitory; some are stimulatory. OCIL inhibits NK cell function via binding to the receptor NKRP1D. Murine OCIL in addition to inhibiting NK cell function inhibits osteoclast differentiation. MAFA clusters with the type I Fc epsilon receptor (FcepsilonRI) and inhibits the mast cells secretory response to FcepsilonRI stimulus. CD72 is a negative regulator of B cell receptor signaling. NKG2D is an activating receptor for stress-induced antigens; human NKG2D ligands include the stress induced MHC-I homologs, MICA, MICB, and ULBP family of glycoproteins Several NKRs have a carbohydrate-binding capacity which is not mediated through calcium ions (e.g. OCIL binds a range of high molecular weight sulfated glycosaminoglycans including dextran sulfate, fucoidan, and gamma-carrageenan sugars). Dectin-1 binds fungal beta-glucans and in involved in the innate immune responses to fungal pathogens. MAFA binds saccharides having terminal alpha-D mannose residues in a calcium-dependent manner. LOX-1 is the major receptor for OxLDL in endothelial cells and thought to play a role in the pathology of atherosclerosis. Some NKRs exist as homodimers (e.g.Lys49, NKG2D, CD69, LOX-1) and some as heterodimers (e.g. CD94/NKG2A). Dectin-1 can function as a monomer in vitro.

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                  ....*....|....*....|....*....|....*....|....*
gi 1622842139  83 CPPNWIIYEKSCYLFSPSLNSWDGSKRQCSQLGSNLIKIDSSKEL 127
Cdd:cd03593     1 CPKDWICYGNKCYYFSMEKKTWNESKEACSSKNSSLLKIDDEEEL 45

Ly49-like protein, N-terminal region; The sequences making up this family are annotated as, or are similar to, Ly49 receptors. These are type II transmembrane receptors expressed by mouse natural killer (NK) cells. They are classified as being activating (e.g.Ly49D and H) or inhibitory (e.g. Ly49A and G), depending on their effect on NK cell function. They are members of the C-type lectin receptor superfamily, and in fact in many family members this region is found immediately N-terminal to a lectin C-type domain (pfam00059).

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                  ....*....|....*....|....*...
gi 1622842139  49 SPPWRLIAVILGILCLVILVIAVVLGTM 76
Cdd:pfam08391   1 SVPWHLIVIALGILCSLLLVTVAVLGTK 28

UL45 protein, carbohydrate-binding C-type lectin-like; This family consists of several UL45 proteins. The herpes simplex virus UL45 gene encodes an 18 kDa virion envelope protein whose function remains unknown. It has been suggested that the 18 kDa UL45 gene product is required for efficient growth in the central nervous system at low doses and may play an important role under the conditions of a naturally acquired infection. This family also contains several Varicellovirus UL45 or gene 15 proteins. The Equine herpesvirus 1 UL45 protein represents a type II membrane glycoprotein which has been found to be non-essential for EHV-1 growth in vitro but deletion reduces the viruses' replication efficiency. Studies have shown that UL45 has a C-type lectin-like fold, suggesting that it might have a carbohydrate-binding function.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622842139  52 WRLIAVILGILCLV-ILVIAVVLGTMGvlSSPCPPNWIIYEKSCYLFSP-SLNSWDGSKRQCSQLGSNLIKIDSSKELIS 129
Cdd:pfam05473  46 GFAIGVLLTMFVIVaTFVFTVPRMALE--SGPCPAEWIGLGDSCIRPDGtPADTYEEAVATCAAYPSKLIPRSTAKLLAA 123

C-type lectin-like domain (CTLD) of the type found in natural killer cell receptors (NKRs); CLECT_NK_receptors_like: C-type lectin-like domain (CTLD) of the type found in natural killer cell receptors (NKRs), including proteins similar to oxidized low density lipoprotein (OxLDL) receptor (LOX-1), CD94, CD69, NKG2-A and -D, osteoclast inhibitory lectin (OCIL), dendritic cell-associated C-type lectin-1 (dectin-1), human myeloid inhibitory C-type lectin-like receptor (MICL), mast cell-associated functional antigen (MAFA), killer cell lectin-like receptors: subfamily F, member 1 (KLRF1) and subfamily B, member 1 (KLRB1), and lys49 receptors. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. NKRs are variously associated with activation or inhibition of natural killer (NK) cells. Activating NKRs stimulate cytolysis by NK cells of virally infected or transformed cells; inhibitory NKRs block cytolysis upon recognition of markers of healthy self cells. Most Lys49 receptors are inhibitory; some are stimulatory. OCIL inhibits NK cell function via binding to the receptor NKRP1D. Murine OCIL in addition to inhibiting NK cell function inhibits osteoclast differentiation. MAFA clusters with the type I Fc epsilon receptor (FcepsilonRI) and inhibits the mast cells secretory response to FcepsilonRI stimulus. CD72 is a negative regulator of B cell receptor signaling. NKG2D is an activating receptor for stress-induced antigens; human NKG2D ligands include the stress induced MHC-I homologs, MICA, MICB, and ULBP family of glycoproteins Several NKRs have a carbohydrate-binding capacity which is not mediated through calcium ions (e.g. OCIL binds a range of high molecular weight sulfated glycosaminoglycans including dextran sulfate, fucoidan, and gamma-carrageenan sugars). Dectin-1 binds fungal beta-glucans and in involved in the innate immune responses to fungal pathogens. MAFA binds saccharides having terminal alpha-D mannose residues in a calcium-dependent manner. LOX-1 is the major receptor for OxLDL in endothelial cells and thought to play a role in the pathology of atherosclerosis. Some NKRs exist as homodimers (e.g.Lys49, NKG2D, CD69, LOX-1) and some as heterodimers (e.g. CD94/NKG2A). Dectin-1 can function as a monomer in vitro.

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                  ....*....|....*....|....*....|....*....|....*
gi 1622842139  83 CPPNWIIYEKSCYLFSPSLNSWDGSKRQCSQLGSNLIKIDSSKEL 127
Cdd:cd03593     1 CPKDWICYGNKCYYFSMEKKTWNESKEACSSKNSSLLKIDDEEEL 45

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.

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gi 1622842139  83 CPPNWIIYEKSCYLFSPSLNSWDGSKRQCSQLGSNLIKIDSSKE 126
Cdd:cd03590     1 CPTNWKSFQSSCYFFSTEKKSWEESRQFCEDMGAHLVIINSQEE 44

C-type lectin protein; Provisional

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gi 1622842139  83 CPPNWIIYEKSCYLFSPSLNSWDGSKRQCSQLGSNLIKID 122
Cdd:PHA02867   49 CPDEWIGYNSKCYYFTINETNWNDSKKLCDVMDSSLIRFD 88

C-type lectin-like protein; Provisional

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622842139  51 PWRLIAVILGILCLVILVIAVVLGTMGVLSSP---------CPPNWIIYEKSCYLFSPSLNSWDGSKRQCSQLGSNLIKI 121
Cdd:PHA02642   47 PEKLYCCIITICILITINLVPIIILMAFKSDTqeptikyvtCPKGWIGFGYKCFYFSEDSKNWTFGNTFCTSLGATLVKV 126

                  ....*.
gi 1622842139 122 DSSKEL 127
Cdd:PHA02642  127 ETEEEL 132

C-type lectin-like protein; Provisional

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gi 1622842139  42 EKGSCVASPPWRLIAVILGILCLVILVI----AVVLGTMGVLSspCPPNWIIYEKSCYLFSPSLNSWDGSKRQCSQLGSN 117
Cdd:PHA03097    3 EKKCCKVTVHWILVPCGSIIIALIALVIilscKLSPGDRSGLN--CRSGWVGYNNKCYTFSENITNKHLAIERCADMDGI 80

                          90
                  ....*....|
gi 1622842139 118 LIKIDSSKEL 127
Cdd:PHA03097   81 LTLIDDQKEV 90