P2X receptor channels show threefold symmetry in ionic charge selectivity and unitary conductance.
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ABSTRACT:
SUBMITTER: Browne LE
PROVIDER: S-EPMC3012030 | biostudies-literature | 2011 Jan
REPOSITORIES: biostudies-literature
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P2X receptor channels show threefold symmetry in ionic charge selectivity and unitary conductance.
Browne Liam E LE Cao Lishuang L Broomhead Helen E HE Bragg Laricia L Wilkinson William J WJ North R Alan RA
Nature neuroscience 20101219 1
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 permeati ...[more]
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