Article

Helical motion of an S4 voltage sensor revealed by gating pore currents

Department of Pharmacology, University of Washington, Seattle, USA.
Channels (Austin, Tex.) (Impact Factor: 2.32). 03/2010; 4(2):75-7. DOI: 10.4161/chan.4.2.10998
Source: PubMed

ABSTRACT

The mechanism by which the voltage sensors of voltage-gated ion channels move gating charge during the activation process is a subject of active debate. In this issue of Channels, Gamal El-Din et al. probe the movements of the S4 voltage sensor of Shaker K(+) channels through clever use of omega gating pore currents generated by paired gating-charge mutations. Their results provide strong support for a sliding helix or helical screw mechanism of gating charge movement.

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