Cloning of GMP-140, a granule membrane protein of platelets and endothelium: sequence similarity to proteins involved in cell adhesion and inflammation

Abstract

GMP-140 is an integral membrane glycoprotein found in secretory granules of platelets and endothelial cells. After cellular activation, it is rapidly redistributed to the plasma membrane. The cDNA-derived primary structure of GMP-140 predicts a cysteine-rich protein with multiple domains, including a "lectin" region, an "EGF" domain, nine tandem consensus repeats related to those in complement-binding proteins, a transmembrane domain, and a short cytoplasmic tail. Some cDNAs also predict a soluble protein with a deleted transmembrane segment. The domain organization of GMP-140 is similar to that of ELAM-1, a cytokine-inducible endothelial cell receptor that binds neutrophils. This similarity suggests that GMP-140 belongs to a new family of inducible receptors with related structure and function on vascular cells.