Figure 7.

Activation of TMEM16A whole-cell currents is potentiated by brevenal. (A) Dose-dependent activation of endogenous TMEM16A whole-cell currents in CFBE airway epithelial cells, by the purinergic agonist ATP. Clamp voltages ± 100 mV in steps of 20 mV. (B) Corresponding current/voltage relationships. (C,D) Activation of whole-cell currents obtained from cells pre-incubated with brevenal (500 nM, 15 min) and corresponding current/voltage relationships. (E) Activation of whole-cell currents in brevenal-incubated cells, in which expression of TMEM16A has been knocked down by treatment with siRNA-TMEM16A (c.f. Supplementary Figure E2). (F) Corresponding current/voltage relationships. Mean ± SEM (number of cells). * significant activation by ATP (p < 0.05, ANOVA). The inhibitor of Ca²⁺-activated KCNN4 K⁺ channels, TRAM-34 (100 nM), was present in all patch clamp experiments to avoid potential activation of Ca²⁺-activated K⁺ channels. # significant difference when compared to the absence of brevenal (p < 0.05, ANOVA). No currents were activated in siRNA-TMEM16A-treated cells.