Mitochondrial dynamics is alteredin pink1−/− zebrafish. (A–L) Representative images of immunohistochemistry performed on wt, pink1−/−, mcu−/− and (pink1; mcu)−/− dissected 4 dpf zebrafish larval brain. DA neurons (red) are marked with anti-TH antibody, mitochondrial structures (green) are marked with anti-Tom20 antibody and DAPI (blue) is shown as nuclear stain. Arrowheads show mitochondrial morphology in muscle fibers. (M–O) Representative images of mitochondrial volumetric analysis in muscle fibers of transgenic wt, pink1−/− and (pink1; mcu)−/− 3 dpf zebrafish expressing mitochondria-localized GFP. Arrowheads point out mitochondrial structures in somites. (P) Graphical representation and statistical analysis of mitochondrial area with one-way ANOVA and post-hoc analysis using Tukey’s multiple comparison test of two different experiments with n=15. There was a significant (*P>0.05) decrease in DA neuronal mitochondrial area in pink1−/− zebrafish when compared to wt; mitochondria area was restored (**P>0.01) in (pink1; mcu)−/− zebrafish. (Q,R) Graphical representation and statistical analyses of muscle mitochondrial volume and sphericity with one-way ANOVA and post-hoc analysis using Tukey’s multiple comparison test of three different experiments with n=30. There was a slight decrease in mitochondrial volume in pink1−/− zebrafish when compared to wt. The cumulative sphericity index is significantly (***P>0.001) reduced in pink1−/− zebrafish, unlike wt and (pink1; mcu)−/− zebrafish.