Fig. 7.

ECHS1‐deficient patient fibroblasts have reduced steady‐state levels of OXPHOS subunits and mature complexes. (A) ECHS1 was detectable in patients P3 and P5, but not in any other patients. NDUFB8 was reduced in all patients, except P5, where NDUFB8 levels were increased, and P7, where NDUFB8 levels were not reduced. UQCRC2 levels were decreased in all patients except P5 and P9. MTCO2 levels were decreased in all patients except P5. ATP5A was decreased in P8 and P9. VDAC1 levels were decreased in P1, P2 and P9. (B) Steady‐state levels of CIII₂ were reduced in P2, P3, P4, P6 and P9 compared to control (CON) mitochondria. CIV levels were reduced in P6, P7 and P8. CV levels were reduced in P3 and P4. CI/CIII₂/CIV supercomplex levels were reduced in P3, P4 and P9. Images shown are representative of three independent experiments. Values shown are mean ± SD, n = 3. *P < 0.05, **P < 0.01 relative to control (CON; Student's two‐tailed t‐test).