Pathways to balance mitochondrial translation and protein import
Priesnitz C, Becker T.
Mitochondria produce the bulk of energy for cellular mechanism via oxidative phosphorylation. Respiratory chain complexes transfer electron from reducing reagents to oxygen. The released energy is used to pump protons across the inner membrane. The F1F0-ATP synthase utilizes the proton gradient to synthesize ATP. Respiratory chain complexes and the ATP synthase are composed of multiple subunits that are encoded in two different genomes . The mitochondrial genome encodes for several core subunits, while the majority of respiratory chain components is nuclear-encoded and produced on cytosolic ribosomes. Consequently, protein synthesis in mitochondria has to be coordinated with import of proteins from the cytosol to build up the function protein machineries. In this review, we summarize the current knowledge about pathways that coordinate import of nuclear-encoded subunits with mitochondrial protein synthesis. We highlight regulatory pathways that fine-tune mitochondrial protein biogenesis upon metabolic and stress signalling.
