Mitochondrial morphology in DJ-1 WT and KO hearts at baseline. Mitochondrial morphology in DJ-1 WT and KO hearts was assessed using EM of hearts isolated at baseline. (a) Representative EM images showing mitochondrial morphology in DJ-1 WT (i) and KO (ii) hearts at baseline; scale bar=2 μM. (b) Assessment of mitochondrial morphology by quantification of the proportion of mitochondria<1 sarcomere in length, equivalent to 1 sarcomere in length and >1 sarcomere in length, n≥3/group. Significance assessed by one-way ANOVA; significance indicated against comparison with DJ-1 WT control (white bars), *P<0.05, **P<0.01, ***P<0.001