Figure 1.

Barttin locks the slow gate of WT rCIC-K1 in a voltage-independent open state. (A and D) Pulse protocols and representative current responses of tsA201 cells expressing WT rClC-K1, either expressed alone (A) or together with barttin (D). (B and E) Voltage dependencies of fast and slow activation and deactivation time constants for WT rClC-K1, either expressed alone (B, n = 6) or together with barttin (E, n = 5 to 9). (C and F) Voltage dependencies of relative probabilities of the channel to be conductive and of relative open probabilities of the fast and slow gates for rClC-K1 without (C, n = 5) or with barttin (F, n = 6). Solid lines in (C) and (F) represent fits with Boltzmann functions. Insets show representative experiments used to determine voltage dependence of slow gate openings.