Tracking S4 movement by gating pore currents in the bacterial sodium channel NaChBac.

ABSTRACT: Voltage-gated sodium channels mediate the initiation and propagation of action potentials in excitable cells. Transmembrane segment S4 of voltage-gated sodium channels resides in a gating pore where it senses the membrane potential and controls channel gating. Substitution of individual S4 arginine gating charges (R1-R3) with smaller amino acids allows ionic currents to flow through the mutant gating pore, and these gating pore currents are pathogenic in some skeletal muscle periodic paralysis syndromes. The voltage dependence of gating pore currents provides information about the transmembrane position of the gating charges as S4 moves in response to membrane potential. Here we studied gating pore current in mutants of the homotetrameric bacterial sodium channel NaChBac in which individua

SUBMITTER: Gamal El-Din TM 

PROVIDER: S-EPMC4113903 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature