The voltage dependence of gating currents of the neuronal CA(v)3.3 channel is determined by the gating brake in the I-II loop.

ABSTRACT: Low-voltage-activated Ca(v)3 Ca(2+) channels have an activation threshold around -60 mV, which is lower than the activation threshold of other voltage-dependent calcium channels (VDCCs). The kinetics of their activation at membrane voltages just above the activation threshold is much slower than the activation kinetics of other VDCCs. It was demonstrated recently that the intracellular loop connecting repeats I and II of all three Ca(v)3 channels contains a so-called gating brake. Disruption of this brake yields channels that activate at even more hyperpolarized potentials with significantly accelerated kinetics. We have compared gating of a wild-type Ca(v)3.3 channel and a mutated ID12 channel, in which the putative gating brake at the proximal part of the I-II loop was removed. Voltage d

SUBMITTER: Karmazinova M 

PROVIDER: S-EPMC3310167 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature