 KCNE1 is primarily known for modulating the cardiac and epithelial Kv channel alfa subunit, KCNQ1.KCNQ1 and KCNE1 form a complex in human ventricular cardiomyocytes that generates the slowly activating K+ current, IKs.Together with the rapidly activating K+ current (IKr), IKs is important for human ventricular repolarization.