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 578821992   1 MYHQPSAPAGIGGPYMFQWNDDRCNMKNNFICKY 34
Cdd:cd03595  116 MYHQPSAPAGQGGPYLFQWNDDNCNMKNNFICKY 149

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.

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gi 578821992   1 MYHQPSAPAGIGGPYMFQWNDDRCNMKNNFICKY 34
Cdd:cd03595  116 MYHQPSAPAGQGGPYLFQWNDDNCNMKNNFICKY 149

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.

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gi 578821992   1 MYHQPSAPAGIGGPYMFQWNDDRCNMKNNFICKY 34
Cdd:cd03595  116 MYHQPSAPAGQGGPYLFQWNDDNCNMKNNFICKY 149