FIGURE 8.

Effect of various compounds on the PS scramblase activity of TMEM16F and on the Cl⁻ channel activity of TMEM16A. A, TMEM16F^−/− IFET transformants expressing TMEM16F were pretreated for 5 min with the indicated concentrations of various Cl⁻ channel inhibitors (tannic acid, EGCG, digallic acid, T16A_inh-A01, NPPB, DIDS, and niflumic acid) followed by stimulation with A23187 and flow cytometry analysis with Cy5-labeled Annexin V. The mean fluorescence intensity observed at 5 min was determined, and the data are expressed as the percentage of fluorescence intensity detected without the compound. Experiments were carried out at least three times, and the average values are plotted with S.D. (error bars). B, 293T cells transfected with the expression vector for TMEM16A were incubated for 5 min with the indicated concentrations of tannic acid, EGCG, digallic acid, or T16A_inh-A01, and membrane currents at 120 mV were measured by whole-cell patch clamp analysis. The data are expressed as the percentage of Cl⁻ current detected without compound. Experiments were carried out at least three times, and the average values are plotted with S.D. (error bars). C, IC₅₀ values of tannic acid, EGCG, digallic acid, and T16Ainh-A01 for TMEM16A (x axis) and -16F (y axis) were determined and plotted.