Biochemical measurements of respiratory chain function.

(A) Relative enzyme activities of respiratory chain enzyme complex I (NADH coenzyme Q reductase, NQR), complex I+III (NADH cytochrome c reductase, NCR), complex II (succinate dehydrogenase, SDH), complex II+III (succinate cytochrome c reductase, SCR) and complex IV (cytochrome c oxidase, COX) in third-instar control (white and grey bars) and bsf KD (black and purple bars) larvae are shown. Bars indicate mean ± SD (^*p<0.05; ^**p<0.01; ^***p<0.001; n = 6-7). (B) Oxygen consumption normalized to protein content in third-instar control (white and grey bars) and bsf KD (black bars) larvae and six-day old flies. Oxygen consumption was assessed in permeabilized larvae and thoraces from six-day old flies by using substrates entering at the level of complex I (CPI), complex II (SUCC), glycerol-3-phosphate dehydrogenase, (G3P) and complex I, II and glycerol-3-phosphate dehydrogenase (CPI-SUCC-G3P), (C) Relative ATP/ADP levels in six-day old bsf KD flies. (D) Lactate/pyruvate ratios in six-day old bsf KD flies.