Figure 3. Mutation carrier–derived lymphoblastoid cell lines (LCLs) show decreased aconitase 2 activity and mitochondrial respiration deficiency compared with control LCLs.

(A) Aconitase enzyme activity in LCL lysates of healthy controls (ACO^c/c) and homozygous patient carriers (ACO2^F414V/F414V) (p = 1.6 × 10⁻⁸). (B) Western blot of corresponding LCL lysates showing equal ACO2 protein levels in healthy controls and homozygous carrier patients. (C) Mitochondrial fraction of LCL lysates show a significant decrease in aconitase enzyme activity in homozygous patient carrier samples (p = 7.4 × 10⁻⁷). (D) ACO2 enzyme activity is unchanged in the cytoplasmic fraction of corresponding LCL lysates (p = 0.11). Data in (A, C and D) are expressed as mean ± SEM, representative experiment of 3 independent experiments, n = 6 time curve measurements per condition; results of the paired t test are indicated. *p < 0.0001.