Figure 2. Example macroscopic current-voltage relationships for wild-type and T338 mutant CFTRs, recorded with symmetrical Cl⁻-containing solutions.

Note the inward rectification observed with some T338 mutants, especially T338N. Patches were held at 0 mV and depolarizing voltage ramps were applied at a rate of 100 mV s⁻¹. Current-voltage relationships were leak subtracted as described in Methods.