A Disease Mutation Causing Episodic Ataxia Type I in the S1 Links Directly to the Voltage Sensor and the Selectivity Filter in Kv Channels.

ABSTRACT: The mutation F184C in Kv1.1 leads to development of episodic ataxia type I (EA1). Although the mutation has been said to alter activation kinetics and to lower expression, we show here that the underlying molecular mechanisms may be more complex. Although F184 is positioned in the "peripheral" S1 helix, it occupies a central position in the 3D fold. We show in cut-open oocyte voltage-clamp recordings of gating and ionic currents of the Shaker Kv channel expressed in Xenopus oocytes that F184 not only interacts directly with the gating charges of the S4, but also creates a functional link to the selectivity filter of the neighboring subunit. This link leads to impaired fast and slow inactivation. The effect on fast inactivation is of an allosteric nature considering that fast inactivation i

SUBMITTER: Petitjean D 

PROVIDER: S-EPMC6605306 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature