P-selectin glycoprotein ligand-1

Selectin P ligand, also known as SELPLG or CD162 (is_associated_with::cluster of differentiation 162), is a human is_associated_with::gene.

P-selectin glycoprotein ligand-1 is a is_associated_with::glycoprotein found on is_associated_with::white blood cells and endothelial cells that binds to is_associated_with::P-selectin (P stands for is_associated_with::platelet), which is one of a family of selectins that includes is_associated_with::E-selectin (endothelial) and is_associated_with::L-selectin (leukocyte). Selectins are part of the broader family of is_associated_with::cell adhesion molecules. PSGL-1 can bind to all three members of the family but binds best (with the highest affinity) to P-selectin.

Posttranslational modification
PSGL-1 protein requires two distinct is_associated_with::posttranslational modifications to gain its selectin binding activity:
 * is_associated_with::sulfation of is_associated_with::tyrosines
 * the addition of the is_associated_with::sialyl Lewis x tetrasaccharide (sLex) to its O-linked is_associated_with::glycans

Function
PSGL-1 is expressed on all is_associated_with::white blood cells and plays an important role in the recruitment of white blood cells into inflamed tissue.

White blood cells normally do not interact with the is_associated_with::endothelium of blood vessels. However, is_associated_with::inflammation causes the expression of cell adhesion molecules (CAM) such as P-selectin on the surface of the blood vessel wall. White blood cells present in flowing blood can interact with CAM. The first step in this interaction process is carried out by PSGL-1 interacting with P-selectin and/or E-selectin on endothelial cells and adherent platelets. This interaction results in "rolling" of the white blood cell on the endothelial cell surface followed by stable adhesion and transmigration of the white blood cell into the inflamed tissue.