hERG currents were isolated as E-4031 sensitive current.

hERG currents overexpressed in hiPSC-CMs were isolated as E-4031-sensitive currents. A,B,C, The data showed families of current traces for WT hERG1a.Ad, hERG1a(R56Q).Ad and hERG1a(R56Q) + i-eag.Ad (top), after the addition of E4031(500 μM; Middle), and digitally subtracted traces to give the E-4031 sensitive currents (bottom). D, I-V relationships for each hERG channel above. The current at the end of depolarizing step was normalized to the maximum tail current and plotted versus voltage. E, Steady-state activation curves for each hERG channel above. All values were plotted as mean ± S.E.M.; n> = 15 cells.