PTPRNs

Receptor-type tyrosine-protein phosphatase-like N (PTPRN or R-PTP-N) family is a group of proteins with large ectodomain with a regulated endocrine specific protein 18 homology domain (RES18HD), and intracellular catalytically impaired protein tyrosine phosphatase domain. PTPRN2 (ICQ512/IA-2/Phogrin) is localized to secretory granules of neuroendocrine cells where it is involved in insulin granule maturation, secretion and traffic, as well as beta-cell proliferation. ¹