Confocal microscopy and image acquisition were performed with a Zeiss LSM710 laser scanning confocal microscope at a magnification of ×40 using procedures described previously (10 (link)). Images were scanned at 1024 × 1024 pixels, with a slice thickness of 1 μM and line and frame average of 4. Sequential scanning of the different channels was used to avoid bleed-through. Imaging settings were first determined for the control conditions in each experiment, which were then maintained for the other experimental conditions. Stacked Z-projections of images were created for DA neuron counts, and cell bodies stained with anti-TH were manually counted. The investigator was blinded to the individual genotype information while performing the neuronal counts. ImageJ software [National Institutes of Health (NIH)] was used to measure the integrated intensity of mito-GFP relative to TH. TH intensity in the 568-nm channel (marking DA neurons) was used to select regions of interest (ROIs). These ROIs were then transferred to the 488-nm channel to measure fluorescence intensity of mito-GFP–labeled mitochondria within the same ROIs.