D U2OS:GFP−parkin cells were treated with DMSO (DMSO), 25 μM antimycin A (anti A), 25 μM antimycin A and 10 μM oligomycin (anti A + oligo), or 20 μM CCCP (CCCP) for two hours, then fixed and immunostained for PDH E2/E3 bp (red) and TOM20 (blue). A merged image of both mitochondrial markers (mito) is shown at the far right. Arrows indicate PDH E2/E3 bp−positive/TOM20−negative structures colocalizing with GFP−parkin (green). Scale bars, 20 μm. 