Pannexin 3 (PANX3)

A pannexin is a member of a vertebrate family of proteins homologous to the invertebrate innexins. Innexins are responsible for forming gap junctions in invertebrates. Pannexins are demonstrated to form channels that allow release of ATP in erythrocytes and taste receptor cells, epoxyeicosatrienoic acids in erythrocytes, while their role as gap junctions is not yet confirmed in vivo. Gap junctions in vertebrates are known to be formed by a much larger family of proteins known as connexins. Bruzzone et al. (2003) cloned Panx3 from a rat hippocampus cDNA library. The deduced 45-kD protein contains 4 transmembrane domains and cytoplasmic N and C termini. Northern blot analysis of several rat tissues detected Panx3 expression only in skin.