(A; 1) pH-dependent G-V shifts in M314K BK channels in nominal 0 Ca²⁺; (2) pH-dependent G-V shifts in M314K BK channels in 200 µM Ca²⁺; (B; 1) pH-dependent G-V shifts in M314K:H365R:H394R channels in nominal 0 Ca²⁺; (2) pH-dependent G-V shifts in M314K:H365R:H394R channels in 200 µM Ca²⁺; (C; 1) comparison of M314K τ_app–V relations between different pH in 0 Ca²⁺; (2) comparison of M314K τ_app–V relations between different pH in 200 µM Ca²⁺; (D; 1) pH-dependent G-V shifts in M314E BK channels in nominal 0 Ca²⁺; (2) pH-dependent G-V shifts in M314E BK channels in 200 µM Ca²⁺; (E; 1) pH-dependent G-V shifts in M314E:H365R:H394R channels in nominal 0 Ca²⁺; (2) pH-dependent G-V shifts in M314E:H365R:H394R channels in 200 µM Ca²⁺; (F; 1) comparison of M314E τ_app–V relations between different pH in 0 Ca²⁺; (2) comparison of M314E τ_app–V relations between different pH in 200 µM Ca²⁺. (See Tables I and II for fitting parameters.) Each point was calculated from a dataset with n ≥ 3.