Fig. 2 (corrected).
Nicotinamide riboside (NR) supplementation provides benefits to Tafazzin mutants. (A,B) The abundance of NAD+ (B) and NADH (A) was measured by mass spectrometry and normalized to total protein levels (six biological repetitions with six flies per repetition, data are mean±s.d., two-way ANOVA, genotype effect, P<0.0001, Tukey post-hoc test). (C) The NAD+:NADH ratio was calculated from the abundances for those molecules (data are mean±s.d., two-way ANOVA, genotype effect, P<0.0001, Tukey post-hoc test). (D,E) NR supplementation restores the endurance of Taz889 flies (log-rank analysis, n=8 vials, 20 flies per vial; D) and the respiratory control ratio (RCR) (six biological replicates, data are mean±s.e.m., n=60 per replicate, genotype effect, P<0.0001, NR effect, P=0.0029, Tukey post-hoc test; E). (F) At day 10, the relative mitochondrial DNA (mtDNA) copy number is not different between Taz889 and control flies, but NR supplementation increases mtDNA in Taz889 flies (n=3 biological replicates, data are mean±s.d., two-way ANOVA, genotype effect, P<0.0001, NR effect, P=0.0006, Tukey post-hoc test). (G) Feeding NR to Taz889 flies does not alter the MLCL:CL ratio (unpaired two-tailed Student's t-test, six biological repetitions with six flies per repetition). (H,I) There is no difference in total MLCL (H) between Taz889 flies with and without NR feeding, but NR-fed Taz889 flies have an increased abundance of total CL (I) (unpaired two-tailed Student's t-test, six biological repetitions with six flies per repetition). *P<0.05, **P<0.01, ***P<0.001, ****P<0.0001; ns, not significant.