Unconventional voltage sensing in an inwardly rectifying potassium channel

Abstract

Inwardly rectifying potassium channels are generally thought to achieve their physiological voltage dependence via an “extrinsic” mechanism involving voltage-dependent block by polyamines. A surprising finding of polyamine-independent gating of Kir4.1/Kir5.1 heteromeric channels suggests a mechanism of voltage dependence arising from interactions with permeating ions.