Fig. 3

Defective respiration and impaired assembly of ETC complexes I-III and SCs in cKO hearts. a Effect of NDUFAB1 ablation on state III oxygen consumption rate (OCR) in isolated mitochondria at the age of 6 or 10 weeks. For each measurement, 100 μg mitochondria were used. Different respiratory substrates were used: malate/glutamate (Mala/glu, 5 mM) for complex I, succinate (Succ, 5 mM) for complex II, glycerol-3-phosphate (G3P, 5 mM) for complex III, and ascorbate (Asc, 2.5 mM)/N,N,N’,N’-tetramethyl-p-phenylenediamine (TMPD, 0.5 mM) for complex IV, and ADP (100 μM) (mean ± s.e.m.; n = 3–14 male mice of per group; *p < 0.05, **p < 0.01 versus WT at the same age). b In-gel activity of SCs and complex I at the age of 6 or 16 weeks. c BN-PAGE immunoblots of individual ETC complexes and SCs at the age of 6 or 16 weeks. SCs were visualized by antibodies against subunits of complex I (CI, NDUFB8), complex III (CIII, UQCRFS1 or UQCRC1), and complex IV (CIV, COX IV). Complex II was visualized by antibody against SDHA, and complex V with antibody against ATPB. d–f Western blots of subunits of complex I (d), complex II (e), and complex III (f) at the age of 6 or 16 weeks. Dagger represents FeS-containing subunits. ATP5A served as the loading control