Different pathways for activation and deactivation in CaV1.2: a minimal gating model.

ABSTRACT: Point mutations in pore-lining S6 segments of CaV1.2 shift the voltage dependence of activation into the hyperpolarizing direction and significantly decelerate current activation and deactivation. Here, we analyze theses changes in channel gating in terms of a circular four-state model accounting for an activation R-A-O and a deactivation O-D-R pathway. Transitions between resting-closed (R) and activated-closed (A) states (rate constants x(V) and y(V)) and open (O) and deactivated-open (D) states (u(V) and w(V)) describe voltage-dependent sensor movements. Voltage-independent pore openings and closures during activation (A-O) and deactivation (D-R) are described by rate constants alpha and beta, and gamma and delta, respectively. Rate constants were determined for 16-channel constructs as

SUBMITTER: Beyl S 

PROVIDER: S-EPMC2737230 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature