P-selectin [SEP] found in taxon
, and Platelet Activation-Dependent Granule to External Membrane Protein (PADGEM). It was first identified in endothelial cells in 1989.
Gene and regulation.
P-selectin is located on chromosome 1q21-q24, spans  50 kb and contains 17 exons in humans. P-selectin is constitutively expressed in megakaryocytes (the precursor of platelets) and endothelial cells. P-selectin expression is induced by two distinct mechanisms. First, P-selectin is synthesized by megakaryocytes and endothelial cells, where it is sorted into the membranes
-selectin transcription in both species. The elevated synthesis of P-selectin may play an important role in the delivery of protein to the cell surface. In ischemic stroke patients, plasma P-selectin concentration was reported to be highly correlated to plasminogen activator inhibitor-1 activity and tissue plasminogen activator activity.
Structure.
P-selectin is found in endothelial cells and platelets where it is stored in Weibel-Palade bodies and α-granules, respectively. In response to inflammatory cytokines such as IL-4 and IL-13, P-selectin