Fig. 6

A, B Comparison of relative abundances of the mitochondrial nd1 gene in the presence of CLO, in wt and polg^{sa9574/sa9574} zebrafish, untreated (A) or treated (B) with Ethidium Bromide (EtBr). polg^+/+ zebrafish recover from EtBr-induced mtDNA depletion while polg^{sa9574/sa9574} mutants remain depleted of mtDNA. (A’, B’) Data in A’ and B’ charts were generated from three different experiments, each containing a pool of six embryos per genotype and treatment condition (N = 6, in triplicate). C Complex I activity in polg^{sa9574/sa9574} adult muscle tissue is significantly lowered, and can be rescued after CLO treatment. Data were generated from three different experiments, each containing a pool of four samples per genotype and treatment condition (N = 4, in triplicate). D–F Retrograde signalling decrease after CLO treatment, based on the expression of the Hif-Hypoxia targets hbbe3 and pfkfb3 (D, E), and the CREB-responsive gene fosab (F); N = 5. G Muscle birefringence, reduced in polg^{sa9574/sa9574} mutants compared to siblings, can be rescued by CLO treatment. G’ Relative intensity (R.I.) quantifications of experiments shown in G; N = 10 per genotype. H The mitochondrial mass, analysed at 6 dpf by mitochondria-targeted EGFP Tg(Hsa.Cox8a:MLS-EGFP) in the skeletal muscle of all polg^sa9574 genotypes, is reduced in homozygotes (compare C with A, B), and can be rescued by CLO treatment (D–F). H’ Relative intensity (R.I.) quantifications of experiments shown in H; N = 9 per genotype. I The atrial diameter (dashed white lines), enlarged in 2-dpf polg morphants (C) compared to not injected (A) and control-injected (B) embryos, can be restored to normal values after CLO treatment (D–F). Cardiac chambers are visualized by Tg(tg:EGFP,myl7:EGFP)^ia300. I’ Quantifications of experiments shown in I; the atrial diameter is expressed in arbitrary units (A.U.); N = 6 per condition. J The heart rate, increased in polg morphants (MO) compared to controls (N.i.; mMO), can be restored to normal values after CLO treatment; N = 10 per condition; Bpm beats per minute. All charts in Fig. 6 display data as mean ± SEM; n.s. not significant; *p < 0.05; **p < 0.01; ***p < 0.001.