The protein encoded by this gene belongs to the family of P2X receptors, which are ATP-gated ion channels and mediate rapid and selective permeability to cations. This gene is predominantly expressed in skeletal muscle, and regulated by p53. The encoded protein is associated with VE-cadherin at the adherens junctions of human umbilical vein endothelial cells. Alternative splicing results in multiple transcript variants. A related pseudogene, which is also located on chromosome 22, has been identified.