Disulfide characterization of CD31 (PECAM)

Publisher Summary This chapter describes the disulfide characterization of CD31 (PECAM). CD31 is a 100 kDa integral membrane glycoprotein found in endothelial intercellular junctions, platelets, and monocytes. CD31 is believed to be involved in the regulation of endothelial cell migration, thus it is probably involved in vascular development, wound repair, and angiogenesis. Although binding of CD31 is homophilic, there is some evidence that it may bind other members of the cellular adhesion molecule family. Common to the adhesion molecules is the immunoglobulin (Ig) homology unit that consists of two β-sheets stabilized by a disulfide bond. Few adhesion molecule disulfide structures are determined in the chapter. Most disulfide structures are assumed by structural homology with other proteins in the same family or superfamily. The adhesion molecules are relatively, hydrophobic, and heavily glycosylated. Deglycosylation of the native protein ( N - and O - sites) reduce the complexity of peptide maps and simplify mass spectral data, allowing for simpler disulfide assignments.