SCIENCEscience.org 3 DECEMBER 2021¥VOL 374 ISSUE 6572 1231
Fig. 3. Fumarate reduction is required to maintain nucleotide biosynthesis
and the mitochondrial membrane potential in cells deficient in O 2
reduction.(A) Schematic depicting the potential impact of alternative oxidase
(AOX) on the accumulation of QH 2 in cells deficient for complex III or IV activity
and the consequences for fumarate reduction. (B) Ratio of ion counts of ubiquinol to
ubiquinone as measured by LC-MS on mitochondria isolated from WT and SDHB
KO 143B cells expressing or not expressing AOX and treated with DMSO or 500 nM
antimycin for 3 hours (mean ± SEM,n= 4 biological replicates per condition).RESEARCH | RESEARCH ARTICLES