SELP
Description
The SELP (selectin P) is a protein-coding gene located on chromosome 1.
P-selectin is a type-1 transmembrane protein encoded by the SELP gene in humans. It acts as a cell adhesion molecule (CAM) on the surface of activated endothelial cells, which line blood vessels, and activated platelets. In resting endothelial cells, P-selectin is stored in granules called Weibel-Palade bodies, while in resting platelets it is stored in α-granules. Other names for P-selectin include CD62P, Granule Membrane Protein 140 (GMP-140), and Platelet Activation-Dependent Granule to External Membrane Protein (PADGEM). It was first discovered in endothelial cells in 1989. The SELP gene is located on chromosome 1q21-q24, spans over 50 kb, and has 17 exons in humans. P-selectin is constitutively expressed in megakaryocytes (platelet precursors) and endothelial cells. Its expression is regulated by two mechanisms: synthesis by megakaryocytes and endothelial cells, followed by sorting into secretory granule membranes.
P-selectin is a calcium-dependent receptor for myeloid cells, specifically neutrophils and monocytes, and binds to carbohydrates on these cell types. It facilitates the interaction between activated endothelial cells or platelets and leukocytes. The ligand that P-selectin recognizes is sialyl-Lewis X. This interaction enables the rapid rolling of leukocytes over vascular surfaces during the initial stages of inflammation through its interaction with SELPLG.
SELP is also known as CD62, CD62P, GMP140, GRMP, LECAM3, PADGEM, PSEL.
