P2X receptor channels show three-fold symmetry in ionic charge selectivity and unitary conductance

Liam Edward Browne (1) , Lishuang Cao (1) , Helen Broomhead (1) , Laricia Bragg (1) , William Wilkinson (1) , R. Alan North (1)

1 Faculty of Medical and Human Sciences

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 Thr339. Replacing Thr339 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 Thr339 from each contributes symmetrically to the open channel permeation pathway.

Mots clés: Channels; Receptors

Liam Edward Browne, Lishuang Cao, Helen Broomhead, Laricia Bragg, William Wilkinson, et al.. P2X receptor channels show three-fold symmetry in ionic charge selectivity and unitary conductance. Nature Neuroscience, 2010, ⟨10.1038/nn.2705⟩. ⟨hal-00601559⟩