Figure 9. C277Y modifies pore properties of hClC-1 channels.

A, representative current recordings from cells internally dialysed with a pipette solution containing 4 mm Cl⁻ and 120 mm Br⁻, NO₃⁻ or I⁻. Dashed lines indicate zero current. B, voltage dependence of current amplitudes obtained from cells internally dialysed with Br⁻ (n = 6), NO₃⁻ (n = 8) or I⁻ (n = 6). C, current amplitudes of different cells at +105 mV plotted versus their reversal potentials demonstrate that reversal potentials were independent from expression levels in transfected cells. The plot includes individual values (open and grey filled symbols) and the mean values ± SEM (black filled symbols: Br⁻, n = 6; NO₃⁻, n = 8; I⁻, n = 6). D, mutation C277Y (black bars: Br⁻, n = 6; NO₃⁻, n = 9; I⁻, n = 6) altered permeability sequence to I⁻ = NO₃⁻ > Br⁻ > Cl⁻ as compared to Cl⁻ > Br⁻ > NO₃⁻ > I⁻ for WT channels (grey bars: Br⁻, n = 6; NO₃⁻, n = 6; I⁻, n = 4).