This gene encodes a member of the guanylin family, and is expressed in the stomach and intestine. This protein functions as an endogenous ligand for the guanylate cyclase-C receptor and stimulates an increase in cyclic GMP, a key component of several intracellular signal transduction pathways. It maybe involved in salt and water secretion into the intestinal lumen as well as the renal tubules, and thus regulate electrolyte homeostasis in these tissues. [provided by RefSeq, Oct 2011]