Referenced in: none

Automatically associated channels: Kv1.3

Title: A structural link between inactivation and block of a K+ channel.

Authors: Christian Ader, Robert Schneider, Sönke Hornig, Phanindra Velisetty, Erica M Wilson, Adam Lange, Karin Giller, Iris Ohmert, Marie-France Martin-Eauclaire, Dirk Trauner, Stefan Becker, Olaf Pongs, Marc Baldus

Journal, date & volume: Nat. Struct. Mol. Biol., 2008 Jun , 15, 605-12

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/18488040

Abstract
Gating the ion-permeation pathway in K(+) channels requires conformational changes in activation and inactivation gates. Here we have investigated the structural alterations associated with pH-dependent inactivation gating of the KcsA-Kv1.3 K(+) channel using solid-state NMR spectroscopy in direct reference to electrophysiological and pharmacological experiments. Transition of the KcsA-Kv1.3 K(+) channel from a closed state at pH 7.5 to an inactivated state at pH 4.0 revealed distinct structural changes within the pore, correlated with activation-gate opening and inactivation-gate closing. In the inactivated K(+) channel, the selectivity filter adopts a nonconductive structure that was also induced by binding of a pore-blocking tetraphenylporphyrin derivative. The results establish a structural link between inactivation and block of a K(+) channel in a membrane setting.