title: P2X receptor channels show threefold symmetry in ionic charge selectivity and unitary conductance.
abstract: In the closed structure of the P2X cation channel, three α-helical transmembrane domains cross the membrane obliquely. In rat P2X2 receptors, these intersect at Thr(339). Replacing Thr(339) by lysine in one, two or three subunits progressively increased chloride permeability and reduced unitary conductance. This implies that the closed-open transition involves a symmetrical separation of the three subunits and that Thr(339) from each subunit contributes symmetrically to the open channel permeation pathway.
authors.affiliation: Faculty of Medical and Human Sciences, and Faculty of Life Sciences, University of Manchester, Manchester, UK.
authors.forename: Liam E
authors.initials: LE
authors.lastname: Browne
authors.forename: Lishuang
authors.initials: L
authors.lastname: Cao
authors.forename: Helen E
authors.initials: HE
authors.lastname: Broomhead
authors.forename: Laricia
authors.initials: L
authors.lastname: Bragg
authors.forename: William J
authors.initials: WJ
authors.lastname: Wilkinson
authors.forename: R Alan
authors.initials: RA
authors.lastname: North
mesh_terms: D000255:Adenosine Triphosphate / Q000502:physiology; D019943:Amino Acid Substitution / Q000502:physiology; D000818:Animals; D002463:Cell Membrane Permeability / Q000502:physiology*; D002712:Chlorides / Q000502:physiology; D008564:Membrane Potentials / Q000502:physiology*; D051381:Rats; D058476:Receptors, Purinergic P2X2 / Q000502:physiology*
chemical_list: D002712:Chlorides; D058476:Receptors, Purinergic P2X2; D000255:Adenosine Triphosphate