Fig. 1

Fig. 1

a Quantitation of murine liver proteome succinylation shows TCA cycle enzymes are targets of lysine succinylation in mice (C57/BL6, n = 10 wild-type, n = 10 Sirt5^−/−). The SCL complex shows higher fold-changes than other TCA cycle enzymes. “Su” in the scheme indicates a succinylation modification that is removed by SIRT5. The boxplot shows the median, the first to third quartile, the 1.5x interquartile ranges, and outliers. b Untargeted metabolomics show more succinyl-CoA and α-ketoglutarate in patient-derived fibroblasts than in control fibroblasts. The color scale indicates fold-change. c Volcano plot of metabolite changes in fibroblasts from SCL patients and control fibroblasts. The red dot shows succinyl-CoA. d SDS-PAGE and western blot analysis of lysine succinylation in fibroblasts cultured in standard culture conditions (proliferative condition) and cells cultured for 5 days in low-serum conditions (non-proliferative condition). Patients (P1–P7) carry disease-causing mutations in SUCLA2. Controls (C1–C3) are fibroblasts from age-matched patients with other mitochondrial diseases. e SDS-PAGE and western blot analysis of lysine succinylation during myoblast differentiation in myotubes (arrow indicates stages of differentiation) of patient with SCL deficiency due to Asp333Gly mutation in SUCLA2. Control is an age-matched patient with a non-mitochondrial disease. GAPDH was used as a loading control, and residual SUCLA2 levels in patient samples are shown. Western blot images are representative results from 10 different independent experiments with similar results. The p-values were calculated with Welch two-sample t-test assuming unequal variance. Source data are provided as a Source Data file. WT = wild-type; SuK = succinyl-lysine, nd = not determined.