Anion currents by Slc26a6 expressed in HEK cells and oocytes. The whole cell current was measured with HEK cells expressing Slc26a6 or the indicated Slc26a6 mutants and with pipette solution containing 142 mM Cl⁻ (A and B) or 140 mM Glu⁻ (C). In A, the membrane potential was clamped at 0 mV, and current recording was begun at bath solution containing 149 mM Cl⁻. Where indicated, bath solution was changed to Cl⁻-free solution containing 145 mM NO₃⁻ or 145 mM SCN⁻. To obtain the I-Vs in B and C, current was recorded by 100 msec RAMPs of −100 to 100 mV. The GFP traces are from cells transfected with GFP only. All other traces are from cells transfected with Slc26a6. (D) The mean ± SEM of three to five experiments. (E) The time course of SCN⁻ current was measured in oocytes expressing Slc26a6 by 100 msec RAMPs of −100 to 100 mV every second. The current at −100 and +60 mV is plotted. The I-Vs in F are from the times indicated by large filled symbols in E. Similar results were obtained in eight experiments.