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 37675377  74 CPPNWIIYEKSCYLFSMSLNSWDGSKRQCWQLGSNLLKIDSSNEL 118
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 37675377  74 CPPNWIIYEKSCYLFSMSLNSWDGSKRQCWQLGSNLLKIDSSNEL 118
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 37675377    40 SPPWRLIAVILGILCLVILVIAVVLGTM 67
Cdd:pfam08391   1 SVPWHLIVIALGILCSLLLVTVAVLGTK 28

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 37675377  74 CPPNWIIYEKSCYLFSMSLNSWDGSKRQCWQLGSNLLKIDSSNEL 118
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 37675377    40 SPPWRLIAVILGILCLVILVIAVVLGTM 67
Cdd:pfam08391   1 SVPWHLIVIALGILCSLLLVTVAVLGTK 28

C-type lectin protein; Provisional

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                 ....*....|....*....|....*....|....*....|...
gi 37675377   74 CPPNWIIYEKSCYLFSMSLNSWDGSKRQCWQLGSNLLKIDSSN 116
Cdd:PHA02867  49 CPDEWIGYNSKCYYFTINETNWNDSKKLCDVMDSSLIRFDNIE 91

C-type lectin-like protein; Provisional

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 37675377   42 PWRLIAVILGILCLVILVIAVVLGTMGVLSSP---------CPPNWIIYEKSCYLFSMSLNSWDGSKRQCWQLGSNLLKI 112
Cdd:PHA02642  47 PEKLYCCIITICILITINLVPIIILMAFKSDTqeptikyvtCPKGWIGFGYKCFYFSEDSKNWTFGNTFCTSLGATLVKV 126

                 ....*.
gi 37675377  113 DSSNEL 118
Cdd:PHA02642 127 ETEEEL 132