Effect of FXYDs on charge movement. (A) Mean transient charge-movement rate for α1β1 alone or coexpressed with FXYD proteins. The rates were calculated from monoexponential fits to the integral of transient currents. (B) Mean normalized Q-V curves for α1β1 alone or when coexpressed with FXYD isoforms. Error bars are SEM in both panels. See also Table 2 (note that the α1β1 and α1β1FXYD1 shown here are those that started at a holding potential of −50 mV).