P2X receptors (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database


P2X receptors (nomenclature as agreed by the NC-IUPHAR Subcommittee on P2X Receptors [46, 134]) have a trimeric topology [118, 132, 177] with two putative TM domains, gating primarily Na+, K+ and Ca2+, exceptionally Cl-. The Nomenclature Subcommittee has recommended that for P2X receptors, structural criteria should be the initial criteria for nomenclature where possible. X-ray crystallography indicates that functional P2X receptors are trimeric and three agonist molecules are required to bind to a single receptor in order to activate it [132, 88, 96, 161]. Native receptors may occur as either homotrimers (e.g. P2X1 in smooth muscle) or heterotrimers (e.g. P2X2:P2X3 in the nodose ganglion [251], P2X1:P2X5 in mouse cortical astrocytes [146], and P2X2:P2X5 in mouse dorsal root ganglion, spinal cord and mid pons [50, 207]. P2X2, P2X4 and P2X7 receptors have been shown to form functional homopolymers which, in turn, activate pores permeable to low molecular weight solutes [229]. The hemi-channel pannexin-1 has been implicated in the pore formation induced by P2X7 [188], but not P2X2 [38], receptor activation.
How to Cite
Di Virgilio, F., Evans, R. J., Falzoni, S., Jarvis, M. F., Kennedy, C., Khakh, B. S., King, B., Pellegatti, P. and Peters, J. A. (2019) “P2X receptors (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database”, IUPHAR/BPS Guide to Pharmacology CITE, 2019(4). doi: 10.2218/gtopdb/F77/2019.4.