Fig. 1.

Loss of Pink1 impairs OXPHOS function in Drosophila. Pink1-KO flies have defects in complexes I and IV driven respiration, and reduced complexes I and IV specific activities. (A) Complex I-dependent respiration with pyruvate/malate as substrates. Compared with the WT control, a statistically significant deficit in O₂ consumption was detected in the Pink1-KO fly (58.6% reduction, n = 4, P = 0.007, Student's t test). (B) Complex IV dependent respiration with TMPD/ascorbate as substrates. Compared with the WT control, a statistically significant deficit in O₂ consumption was detected in the Pink1-KO fly (58.3% reduction, n = 4, P = 0.007, Student's t test). In the spectrophotometric measurement of complex I (C) and complex IV (D) activities, the Pink1-KO fly had a 53% reduction in complex I (n = 8; P = 0.0001; ANOVA) and 47% reduction in complex IV (n = 8; P = 0.0001; ANOVA). (E) Measurement of ATP synthesis with pyruvate/malate as substrates revealed a significant reduction in ATP synthesis (60% reduction; n = 19; P = 0.001; ANOVA) in the Pink1-KO fly. All of the measurements were normalized by citrate synthase activity. (F) PDH was used as a mitochondrial quantity control. Equal amounts of mitochondria were used for all experiments. Asterisks indicate statistical significance.