Fig. 4. Kv1.4 mutants in the N terminus.

a Sequence of Kv1.4 N terminus with C13 and H16 highlighted. Representative whole-cell current traces of Kv1.4 channels in HEK293T cells in response to membrane depolarization to 50 mV from a holding potential of −100 mV before (black) and 300 s after application (red) of bath solution with 1 mM NaHS (left) or 10 μM Na₂S₄ (right) for Kv1.4 mutants C13S (top), H16R (middle), and C13S:H16R (bottom). pH 7.4. b Comparison of the effect of 1 mM NaHS on the inactivation indices (I_{200 ms} / I_peak) of the indicated Kv1.4 mutants compared with the wild type (wt) as shown in Fig. 1. c As in panel b) but with 10 μM Na₂S₄ application at time zero; the reference wt data were previously shown in Fig. 3). Data in b-c are means±SEM with n in parentheses