We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Coupling of activation and inactivation gate in a K<sup>+</sup>-channel: potassium and ligand sensitivity.
- Authors
Ader, Christian; Schneider, Robert; Hornig, Sönke; Velisetty, Phanindra; Vardanyan, Vitya; Giller, Karin; Ohmert, Iris; Becker, Stefan; Pongs, Olaf; Baldus, Marc
- Abstract
Potassium (K+)-channel gating is choreographed by a complex interplay between external stimuli, K+ concentration and lipidic environment. We combined solid-state NMR and electrophysiological experiments on a chimeric KcsA–Kv1.3 channel to delineate K+, pH and blocker effects on channel structure and function in a membrane setting. Our data show that pH-induced activation is correlated with protonation of glutamate residues at or near the activation gate. Moreover, K+ and channel blockers distinctly affect the open probability of both the inactivation gate comprising the selectivity filter of the channel and the activation gate. The results indicate that the two gates are coupled and that effects of the permeant K+ ion on the inactivation gate modulate activation-gate opening. Our data suggest a mechanism for controlling coordinated and sequential opening and closing of activation and inactivation gates in the K+-channel pore.
- Subjects
ELECTROPHYSIOLOGY; HYDROGEN-ion concentration; GLUTAMIC acid; LIGANDS (Biochemistry); POTASSIUM
- Publication
EMBO Journal, 2009, Vol 28, Issue 18, p2825
- ISSN
0261-4189
- Publication type
Article
- DOI
10.1038/emboj.2009.218