Extended Data Fig. 6: A metabolon comprising ETFDH, CIII, and the regulator of Q biosynthesis, COQ2.
a) Total Q10 levels in control (CRL) and patient-derived fibroblasts (M2, M3, M4, M9). n = 3. b) Left panel, schematic represents Q biosynthesis. Right panel, heat-map representation of quantitative proteomic analysis (TMT) of CRL and ETFDH-ko myoblasts. A t-tests to compare groups in a pairwise fashion was used. A (-) log2 p-value > 4 was considered statistically significant. A 3-color palette was used: white, non-significance; progressively more saturated values of blue and red indicate increased significance. Blue and red also means downregulated or upregulated protein, respectively. c) Immunocapture (IP) of COQ2 blotted with anti-UQCRC2 and ETFDH antibodies; and IP of UQCRC2 blotted with anti-ETFDH and anti-COQ2 antibodies in Skm extracts. P.C. Positive control (total extract). In the square, common interactors in the proteomic analysis of the 4 IPs. Graphs in lower panel represents the number of tryptic peptides (NOP) plotted against the number of PSM of each protein. The stoichiometry of ETFDH-CIII is estimated by plotting the observed PSM per protein from each complex against their effective NOP; the stoichiometry between the two complexes is estimated as the ratio of the slopes from each one of them. d) Proximity ligation assay (PLA) between ETFDH-UQCRC2, ETFDH-COQ2 and UQCRC2-COQ2 in control (CRL) and ETFDH-ko myoblasts. Quantification in right histograms. 5 images/condition, n = 3. Results are shown as the mean ± SEM of the indicated n. *, **, ***, **** p < 0.05; 0.01, 0.001 and 0.0001 when compared to CRL by two-tailed Student’s t-test (d) and one-way ANOVA with Dunnett’s test (a).
