Transcriptomics study on the effect of alternative oxidase expression in Bcs1l mutant (S78G) mice (Mus musculus)

We crossed a Ciona intestinalis AOX transgene into RC complex III (cIII) deficient Bcs1lp.S78G knock-in mice, displaying multiple visceral manifestations and premature death. The homozygotes expressing AOX were viable and their median survival was extended from 210 to 590 days due to permanent prevention of lethal cardiomyopathy. AOX also prevented renal tubular atrophy and cerebral astrogliosis, but not liver disease, growth restriction, or lipodystrophy, suggesting distinct tissue-specific pathogenetic mechanisms. Cardiac mitochondrial ultrastructure, mitochondrial respiration, and pathological transcriptome and metabolome alterations were essentially normalized by AOX, showing that the restored electron flow upstream of cIII was sufficient to prevent cardiac energetic crisis and detrimental decompensation.