William I. Sivitz

We examined mitochondrial respiration initiated at mitochondrial complex II in mice with varying degrees of brown adipose tissue UCP1 expression. We show that, by affecting inner membrane potential, UCP1 expression determines reverse electron transport from complex II to complex I and, consequently, the NADH/NAD + ratio. Accordingly, this regulates the level of oxaloacetate accumulation and the extent of oxaloacetate inhibition of complex II