Summary
P-selectin is a transmembrane protein that resides within the alpha granule membrane
of unstimulated platelets. The “extracellular” domains face into the lumen of the
granule and the cytoplasmic tail extends into the platelet cytoplasm. Upon platelet
stimulation, P-selectin is phosphorylated and translocated to the plasma membrane
via a secretory pathway. P-selectin in the plasma membrane surface is exposed and
serves as a cell adhesion receptor to interact with other cell receptors, including
PSGL-1 and GPIb. P-selectin upregulates tissue factor in monocytes and leads to leukocyte
accumulation in areas of vascular injury associated with thrombosis and inflammation.
Key words
P-selectin - selectin - PSGL-1 - platelet - alpha granule