Figure 7. Example current-voltage relationships recorded under biionic conditions with the named anion substituted for Cl⁻ in the intracellular solution.

The differences in reversal potential between wild-type and different T338 mutants reflect large underlying changes in anion selectivity. Patches were held at 0 mV and depolarizing voltage ramps were applied at a rate of 37.5–62.5 mV s⁻¹. Current-voltage relationships were leak subtracted as described in Methods.