This gene encodes an incretin hormone and belongs to the glucagon superfamily. The encoded protein is important in maintaining glucose homeostasis as it is a potent stimulator of insulin secretion from pancreatic beta-cells following food ingestion and nutrient absorption. This gene stimulates insulin secretion via its G protein-coupled receptor activation of adenylyl cyclase and other signal transduction pathways. It is a relatively poor inhibitor of gastric acid secretion. [provided by RefSeq, Jul 2008]