The protein encoded by this gene plays a direct regulatory role in calcium-ion-dependent exocytosis in both endocrine and exocrine cells and plays a key role in insulin secretion by pancreatic cells. This gene is likely a tumor suppressor. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jun 2010] see less The protein encoded by this gene plays a direct regulatory role in calcium-ion-dependent exocytosis in both endocrine and exocrine cells and plays a key role in insulin secretion by pancreatic cells. This gene is likely a tumor suppressor. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jun 2010]