PINK1 Protects against Oxidative Stress by Phosphorylating Mitochondrial Chaperone TRAP1
Figure 6
PINK1 Depletion Increases Cytochrome c Release from Mitochondria
(A) PC12 cells transfected with the indicated siRNA or vehicle (control) were treated with 400 μM H2O2 for the indicated times. The levels of cytochrome c (Cyt. c) and actin in the cytosol were determined by immunoblotting with anti-cytochrome c and anti-actin antibodies.
(B) The level of cytochrome c released to the cytosol is normalized to the level of actin in each cell sample. Data represent mean ± SEM from three independent experiments. *Significantly different from the corresponding H2O2-treated control cells (p < 0.01). AU, arbitrary units.
(C) PC12 cells co-transfected with pEGFP and vehicle (control) or indicated siRNAs were treated with 400 μM H2O2 for 16 h. Cell morphology was imaged by using phase-contrast microscopy (grey), transfected cells were visualized by the green fluorescence emitted by green fluorescent protein (GFP), and the cellular distribution of cytochrome c was detected by immunostaining with anti-cytochrome c antibody (red). Transfected cells with mitochondrial cytochrome c staining are indicated by arrows, and those with diffuse, cytosolic cytochrome c staining are indicated by arrowheads. Scale bar, 10 μm.
(D) Quantification of the percentage of transfected cells showing cytochrome c release. Data represent mean ± SEM from three independent experiments. *Significantly different from the H2O2-treated control cells (p < 0.05).