(C) Parkin-mediated ubiquitination limits BAK activation. HeLa+HA-Parkin cells were treated with antimycin A and oligomycin (AO) for 2 h prior to induction of apoptosis with 1 µM of each of the BH3 mimetics ABT-737 and S63485 (BH3 mim) for 1 h. Intracellular flow cytometry was performed using the conformation-specific anti-BAK antibody G317-2. Representative histograms are shown and the fold increase in mean fluorescence intensity (MFI) is plotted from three independent experiments with error bars showing SD. Data are normalised to untreated control. 