Molecular cloning and characterization of a novel orphan receptor (P2P) expressed in human pancreas that shows high structural homology to the P2U purinoceptor

Abstract Here we report the cloning of a gene encoding a new member of the superfamily of G protein-coupled receptors. The gene encodes a protein of 365 amino acids closely resembling two recently cloned nucleotide binding receptors, called P 2U and P 2Y purinoceptors (71% and 49% sequence identity within the transmembrane domains, respectively). Our studies show that this new putative purinoceptor (designated P 2P ) is encoded by an intronless single copy gene that is exclusively expressed in pancreas, in contrast to the P 2U and the P 2Y purinoceptors which are widely distributed throughout the periphery. The identification of a pancreas-specific human putative P 2 purinoceptor makes it attractive to speculate that the reported actions of ADP/ATP analogues in pancreas on insulin secretion are mediated through this receptor.