Rieger 2021 EMBO Rep
Rieger B, Arroum T, Borowski MT, Villalta J, and Busch KB (2021) Mitochondrial F1FO ATP synthase determines the local proton motive force at cristae rims. EMBO Rep 22:e52727. |
Rieger B, Arroum T, Borowski MT, Villalta J, and Busch KB (2021) EMBO Rep
Abstract: The classical view of oxidative phosphorylation is that a proton motive force (PMF) generated by the respiratory chain complexes fuels ATP synthesis via ATP synthase. Yet, under glycolytic conditions, ATP synthase in its reverse mode also can contribute to the PMF. Here, we dissected these two functions of ATP synthase and the role of its inhibitory factor 1 (IF1) under different metabolic conditions. pH profiles of mitochondrial subβcompartments were recorded with high spatial resolution in live mammalian cells by positioning a pH sensor directly at ATP synthaseβs F1 and FO subunits, complex IV and in the matrix. Our results clearly show that ATP synthase activity substantially controls the PMF and that IF1 is essential under OXPHOS conditions to prevent reverse ATP synthase activity due to an almost negligible ΞpH. In addition, we show how this changes lateral, transmembrane, and radial pH gradients in glycolytic and respiratory cells.
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MitoFit 2022 pmF