ML277 is a selective small-molecule activator of the KCNQ1 potassium channel, making it a valuable tool in the study of cardiac and epithelial ion channel function. It is primarily used in research to enhance the activity of KCNQ1 channels, which play a critical role in regulating the heart's electrical activity, particularly the repolarization phase of the cardiac action potential. By potentiating KCNQ1 current, ML277 helps investigate mechanisms underlying long QT syndrome and other arrhythmias linked to ion channel dysfunction. In addition to cardiac applications, ML277 has been explored in studies related to epithelial secretion, as KCNQ1 is expressed in tissues such as the gastrointestinal tract and pancreas, where it contributes to salt and fluid transport. Researchers use ML277 to probe the physiological impact of enhanced KCNQ1 activity in these systems, offering insights into potential therapeutic strategies for diseases involving ion transport abnormalities. Its selectivity makes it a useful pharmacological agent for distinguishing KCNQ1-specific effects from those mediated by other potassium channels.