Figure 4

pH dependency of Ppk19-mediated currents. (A-C) Representative whole-cell recording traces at ± 60 mV (left) and current–voltage relationships (right) upon extracellular pH stimulation in untransfected (A), parental vector (mock)- (B) and ppk19-transfected CHO-K1 cells (C). Currents indicated as dots of different colors below the traces were used to extract current–voltage relationships. Inset: expanded view. (D) pH response curves were calculated using the Hill equation from acid responses at − 60 mV for untransfected, ppk19-, and parental vector (mock)-transfected CHO-K1 cells. (E) Inward currents at − 60 mV during pH 3.5 exposure in untransfected, ppk19-, and parental vector (mock)-transfected CHO-K1 cells. **, p < 0.01 by unpaired two-tailed t-test.