P-selectin

P-selectin (also known as CD62P) is a protein that is stored in the alpha granules of platelets and Weibel-Palade bodies of endothelial cells. Upon activation, P-selectin is transported to the cell surface and plays a key role in the initial recruitment of leukocytes during inflammatory responses.

Structure

P-selectin is a type I membrane protein that belongs to the selectin family. It consists of a large, highly glycosylated extracellular domain, a single transmembrane domain, and a short cytoplasmic tail. The extracellular domain contains a lectin-like domain, an epidermal growth factor (EGF)-like domain, and a series of consensus repeats similar to those found in complement binding proteins.

Function

P-selectin mediates the interaction of circulating leukocytes with endothelial cells and platelets. This interaction is crucial for the recruitment of leukocytes to the site of injury during inflammation. P-selectin binds to a specific ligand, P-selectin glycoprotein ligand-1 (PSGL-1), which is expressed on the surface of most leukocytes.

Clinical significance

P-selectin has been implicated in various diseases such as atherosclerosis, thrombosis, cancer, and inflammatory diseases. Elevated levels of soluble P-selectin have been found in the blood of patients with these conditions, suggesting that it may serve as a potential biomarker.

See also

• Selectin
• Leukocyte
• Inflammation
• Atherosclerosis
• Thrombosis
• Cancer