Fig. 3.

Western blot studies and a [³⁵S] translational assay give insight into molecular effect of GFM2 variants. a Fibroblast Western blot panel, with SDHA as a loading control. The panel demonstrates decreased steady-state levels of NDUFB8 (complex I), CORE 2 and CYT B (complex III) and COX I and COX II (complex IV) in the fibroblasts of Patient 2, but unchanged levels in the fibroblasts of Patient 1. b Skeletal muscle Western blot panel for Patient 1, with SDHA as a loading control. A complex IV deficiency is apparent, with decreased steady-state levels of COX I and COX II. Steady-state levels of other OXPHOS subunits remain unchanged. Levels of mtEFG2 protein are ~ 50% of controls. c [³⁵S] methionine/cysteine incorporation in growing fibroblasts as a measure of de novo mitochondrial protein synthesis showed no difference between either Patient 1 or Patient 2 and the controls using Coomassie stain as loading control (bottom panel)