Human cardiac Kv4.3 channels are regulated by EGFR kinase and SRC-family kinases

The transient outward potassium current Ito (encoded by Kv4.3) plays an important role in the phase 1 rapid repolarization of cardiac action potentials in the heart. It further determines the duration of repolarization and the propensity to cardiac arrhythmias. Modulation of Ito by intracellular signal transduction is not understood. The present study was designed to determine whether hKv4.3 channel (alpha-subunit of human cardiac Ito) is regulated by protein tyrosine kinases (PTKs) in HEK 293 cells stably expressing human Kv4.3 gene using a whole-cell patch clamp technique, immunoprecipitation and western blot. It was found that hum...postprin