The Fast Component of hERG Gating Charge: An Interaction between D411 in the S1 and S4 Residues.

ABSTRACT: Kv11.1 (hERG) is a voltage-gated potassium channel that shows very slow ionic current activation kinetics, and an unusual underlying biphasic gating charge movement with fast and slow components that differ greatly in time course. The structural basis and role of the fast component of gating charge (Q_fast) is unclear, and its relationship to the slow activation of hERG channels is not understood. In this study we have used the cut-open oocyte voltage-clamp technique to investigate the relationship of fast gating charge movement-to-residue interactions between D411 at the bottom of the S1, and lower S4 domain charged and uncharged residues. Neutralization of D411 or K538 and V535A prevented Q_fast and greatly accelerated overall charge movement. Voltage-clamp fluorometr

SUBMITTER: Dou Y 

PROVIDER: S-EPMC5685676 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature