Expression and function of IA-2 family proteins, unique neuroendocrine-specific protein-tyrosine phosphatases

摘要: IA-2 (also known as islet cell antigen ICA-512) and IA-2β phogrin, phosphatase homologue in granules of insulinoma) are major autoantigens insulin-dependent diabetes mellitus (IDDM). Autoantibodies against both proteins expressed years before clinical onset, they become predictive markers for high-risk subjects. However, the role these genes IDDM pathogenesis has been reported fairly negative by recent studies. type I transmembrane that possess one inactive protein-tyrosine (PTP) domain cytoplasmic region, act constituents regulated secretory pathways various neuroendocrine types including pancreatic β-cells. Existence homologues different species suggests a fundamental function. Studies knockout animals have shown their involvement maintaining hormone content, however, specific steps pathway functions well molecular mechanisms content regulation still unknown. More studies suggested novel function showing contribute to β-cell growth. This review attempts show possible biological family, focusing on expression localization cells.