Fig. 3: Influence of Kv4.2–KChIP1 interface mutations on KChIP1 modulation.
From: Structural basis of gating modulation of Kv4 channel complexes
a, Normalized and superposed current traces of wild-type Kv4.2 (WT) (grey) and each mutant (black) with (right) or without (left) KChIP1 elicited by test pulses of 40 mV for the qualitative comparisons of inactivation kinetics (n = 8 independent experiments). b–e, Comparisons of the recovery rate from inactivation in wild-type Kv4.2 with (black) or without (black and dashed) KChIP1, and in each mutant Kv4.2 (F474A/H478A (b), H480A (c), L482A/L485A (d) and H491A/F493A/V494A (e)) with (coloured) or without (coloured and dashed) KChIP1. The currents were elicited by a two-pulse protocol (inset) using prepulses (500 ms) and test pulses (100 ms) at 40 mV with an interpulse interval (Δt) of the duration from 10 to 490 ms at −100 mV. The fractional recovery at each point was determined by normalizing the peak current amplitude of the test pulse by the amplitude of the prepulse. Symbols and bars represent mean ± s.e.m. (n = 8). Lines represent single-exponential fits. For the Kv4.2(F474A/H478A) with KChIP1 and Kv4.2(H480A) with KChIP1 conditions, only data obtained using prepulses from 10 ms to 90 ms were used for single-exponential fits, owing to reduced fractional recovery at longer prepulses.
