Electrophysiological Analysis of the Cardiac KV Channel with the New Point Mutation Found in the Patient with LQTS

Abstract

Voltage-dependent cation channels Kv7.1 encoded by the KCNQ1 genes play an important role in the repolarization of cardiac cells and the maintenance of normal duration of cardiac action potential. In cardiac muscle tissue, Kv7.1 is expressed together with the accessory KCNE1 beta-subunit to form a functionally active channel that provides a slow repolarization current. To date, more than 100 mutations (mainly single nucleotide variations, SNV) are known to affect the activity of the Kv7.1 channel, altering the kinetics of activation and interaction with regulatory subunits, or disrupting traffic toward the cell membrane.