Conversion of an instantaneous activating K+ channel into a slow activating inward rectifier
Baumeister, D. and Hertel, B. and Schroeder, I. and Gazzarrini, S. and Kast, S.M. and Van Etten, J.L. and Moroni, A. and Thiel, G.
Volume: 591 Pages: 295-303
The miniature channel, Kcv, is a structural equivalent of the pore of all K+ channels. Here, we follow up on a previous observation that a largely voltage-insensitive channel can be converted into a slow activating inward rectifier after extending the outer transmembrane domain by one Ala. This gain of rectification can be rationalized by dynamic salt bridges at the cytosolic entrance to the channel; opening is favored by voltage-sensitive formation of salt bridges and counteracted by their disruption. Such latent voltage sensitivity in the pore could be relevant for the understanding of voltage gating in complex Kv channels. © 2016 Federation of European Biochemical Societies