Shifts in the selectivity filter dynamics cause modal gating in K⁺ channels.

ABSTRACT: Spontaneous activity shifts at constant experimental conditions represent a widespread regulatory mechanism in ion channels. The molecular origins of these modal gating shifts are poorly understood. In the K⁺ channel KcsA, a multitude of fast activity shifts that emulate the native modal gating behaviour can be triggered by point-mutations in the hydrogen bonding network that controls the selectivity filter. Using solid-state NMR and molecular dynamics simulations in a variety of KcsA mutants, here we show that modal gating shifts in K⁺ channels are associated with important changes in the channel dynamics that strongly perturb the selectivity filter equilibrium conformation. Furthermore, our study reveals a drastically different motional and conformational selectivit

SUBMITTER: Jekhmane S 

PROVIDER: S-EPMC6328603 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature