Proton currents constrain structural models of voltage sensor activation.
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ABSTRACT:
SUBMITTER: Randolph AL
PROVIDER: S-EPMC5065317 | biostudies-literature | 2016 Aug
REPOSITORIES: biostudies-literature
Publications
Proton currents constrain structural models of voltage sensor activation.
Randolph Aaron L AL Mokrab Younes Y Bennett Ashley L AL Sansom Mark Sp MS Ramsey Ian Scott IS
eLife 20160830
The Hv1 proton channel is evidently unique among voltage sensor domain proteins in mediating an intrinsic 'aqueous' H<sup>+</sup> conductance (G<sub>AQ</sub>). Mutation of a highly conserved 'gating charge' residue in the S4 helix (R1H) confers a resting-state H<sup>+</sup> 'shuttle' conductance (G<sub>SH</sub>) in VGCs and Ci VSP, and we now report that R1H is sufficient to reconstitute G<sub>SH</sub> in Hv1 without abrogating G<sub>AQ</sub>. Second-site mutations in S3 (D185A/H) and S4 (N4R) e ...[more]
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