Questioning the functional relevance of mitochondrial supercomplexes by time-resolved analysis of the respiratory chain
2011; National Academy of Sciences; Volume: 108; Issue: 45 Linguagem: Inglês
10.1073/pnas.1109510108
ISSN1091-6490
AutoresMartin Trouillard, Brigitte Meunier, Fabrice Rappaport,
Tópico(s)ATP Synthase and ATPases Research
ResumoMitochondria are the powerhouses of eukaryotic cells as they feed metabolism with its major substrate. Oxidative-phosphorylation relies on the generation, by an electron/proton transfer chain, of an electrochemical transmembrane potential utilized to synthesize ATP. Although these fundamental principles are not a matter of debate, the emerging picture of the respiratory chain diverges from the linear and fluid scheme. Indeed, a growing number of pieces of evidence point to membrane compartments that possibly restrict the diffusion of electron carriers, and to supramolecular assembly of various complexes within various kinds of supercomplexes that modulate the thermodynamic and kinetic properties of the components of the chain. Here, we describe a method that allows the unprecedented time-resolved study of the respiratory chain in intact cells that is aimed at assessing these hypotheses. We show that, in yeast, cytochrome c is not trapped within supercomplexes and encounters no particular restriction to its diffusion which questions the functional relevance of these supramolecular edifices.
Referência(s)