Biophysical properties of potassium ion channels: potential targets to combat cardiac arrhythmia

Synopsis

Potassium-selective ion channel proteins are ubiquitously expressed in cardiac muscle. Here, potassium channels orchestrate repolarization of the cell membrane following the electrical excitation that drives each heartbeat, and they are thus important mediators of cardiac rhythm. This is demonstrated by the association of inherited mutations in potassium channel genes, which alter their biophysical properties, with sudden cardiac death. In this talk, I will discuss the biophysical properties of key potassium channels and how kinetic and steady-state electrophysiological and structural dynamics measurements of channel gating can provide insight into the physiological and pathophysiological role of potassium channels. I will also present some recent data that highlight possible biophysical features that may be targeted to stabilize channels in the open state in order to provide a gain-of-function and perhaps protect against cardiac arrhythmia.