This gene encodes a member of the neuropeptide Y (NPY) family of peptides. The encoded preproprotein is proteolytically processed to generate two alternative peptide products that differ in length by three amino acids. These peptides, secreted by endocrine cells in the gut, exhibit different binding affinities for each of the neuropeptide Y receptors. Binding of the encoded peptides to these receptors mediates regulation of pancreatic secretion, gut mobility and energy homeostasis. Rare variations in this gene could increase susceptibility to obesity and elevated serum levels of the encoded peptides may be associated with anorexia nervosa.