Purification and characterization of a major phosphatidylserine-binding phosphoprotein from human platelets.

摘要: We describe the isolation, lipid-binding properties and partial amino acid sequence of PS-p68, a novel 68 kDa phosphatidylserine-binding protein from human platelets. PS-p68 is an abundant constituent platelets, accounting for 0.5-0.75% total cell protein. It was purified platelet cytosol by affinity chromatography. Amino analysis yielded no similarity to identified proteins. In contrast with most known phospholipid-binding proteins, does not bind Ca2+ require its binding phosphatidylserine. Phosphatidylserine inhibited phosphatidic alkylphospholipids. isolated as major phosphoprotein 32P-labelled platelets found function kinase C substrate in vitro. However, treatment intact phorbol 12-myristate 13-acetate, thrombin or carbacyclin did increase phosphorylation. Platelets appear be only blood cells containing which detected neutrophils, monocytes lymphocytes.