Sodium channel activation gating is affected by substitutions of voltage sensor positive charges in all four domains.

ABSTRACT: The role of the voltage sensor positive charges in the activation and deactivation gating of the rat brain IIA sodium channel was investigated by mutating the second and fourth conserved positive charges in the S4 segments of all four homologous domains. Both charge-neutralizing (by glutamine substitution) and -conserving mutations were constructed in a cDNA encoding the sodium channel alpha subunit that had fast inactivation removed by the incorporation of the IFMQ3 mutation in the III-IV linker (West, J.W., D.E. Patton, T. Scheuer, Y. Wang, A.L. Goldin, and W.A. Catterall. 1992. 89:10910-10914.). A total of 16 single and 2 double mutants were constructed and analyzed with respect to voltage dependence and kinetics of activation and deactivation. The most significant effects were observed

SUBMITTER: Kontis KJ 

PROVIDER: S-EPMC2229375 | biostudies-literature | 1997 Oct

REPOSITORIES: biostudies-literature