FIGURE 3.

Pore mutants of hKv7.4 channels did not produce measurable currents. A, characteristic WT current traces recorded from a holding potential of −80 mV and activated from −110 mV to 30 mV with ΔV of 10 mV as described in the legend for Fig. 2. B–F, using similar activation voltage steps as described in A, CHO cells transfected with hKv7.4 MT channels, with point mutations at the pore region of the channel, namely L274H (B), W276S (C), L281S (D), G285C (E), and G296S (F), were assessed. None of the pore region mutants yielded detectable current. G, current density (in pA/pF)-voltage relations of the wild-type and mutant channels. Each data set designated with symbols shown represents the mean of 15 cells.