Blue native polyacrylamide gel electrophoresis (BN-PAGE) was performed by isolating mitochondrial proteins from mutant and control cell lines, as detailed previously (58 (link),59 (link)). Samples containing 30 μg of total cellular proteins were separated on 3–12% Bis–Tris Native PAGE gel. The total OXPHOS Human WB Antibody Cocktail was applied as primary antibodies for this experiment. Peroxidase AffiniPure goat anti-mouse IgG and goat anti-rabbit IgG (Jackson) were used as secondary antibodies and protein signals were detected using the ECL system (CWBIO).