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.
Jiyao W et al.(2023). "The conserved domain database in 2023.",