Description
CD157, a member of the CD38 gene family, is an NAD- metabolizing ectoenzyme and a signaling molecule whose role in polarization, migration, and diapedesis of human granulocytes has been documented. Ectoenzymes include a heterogeneous group of surface molecules with multiple functions. In addition to interacting with specific substrates, many of them participate in leukocyte activation and migration. In some cases, ectoenzymes exert enzymatic control of leukocyte trafficking. Along with CD38, human CD157 constitutes the NAD glycohydrolase/ADP-ribosyl cyclase gene family. These two molecules share 36% of their protein sequence, including 10 cysteine residues forming intrachain disulfide bonds. However, they differ in structure, with CD157 being a glycosylphosphatidylinositol