mTORC1 Controls Mitochondrial Activity and Biogenesis through 4E-BP-Dependent Translational Regulation

Department of Biochemistry, McGill University, Montreal, QC H3A 1A3, Canada
Cell metabolism (Impact Factor: 17.57). 11/2013; 18(5):698-711. DOI: 10.1016/j.cmet.2013.10.001
Source: PubMed


mRNA translation is thought to be the most energy-consuming process in the cell. Translation and energy metabolism are dysregulated in a variety of diseases including cancer, diabetes, and heart disease. However, the mechanisms that coordinate translation and energy metabolism in mammals remain largely unknown. The mechanistic/mammalian target of rapamycin complex 1 (mTORC1) stimulates mRNA translation and other anabolic processes. We demonstrate that mTORC1 controls mitochondrial activity and biogenesis by selectively promoting translation of nucleus-encoded mitochondria-related mRNAs via inhibition of the eukaryotic translation initiation factor 4E (eIF4E)-binding proteins (4E-BPs). Stimulating the translation of nucleus-encoded mitochondria-related mRNAs engenders an increase in ATP production capacity, a required energy source for translation. These findings establish a feed-forward loop that links mRNA translation to oxidative phosphorylation, thereby providing a key mechanism linking aberrant mTOR signaling to conditions of abnormal cellular energy metabolism such as neoplasia and insulin resistance.

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Available from: Ivan Topisirovic, Jun 08, 2014
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    • "Eukaryotic translation initiation factor 4E (eIF4E)-binding proteins (4E-BP) prevent translation of targets including nuclear encoded mitochondrial protein mRNAs including TFAM (transcription factor A, mitochondrial ) and subunits of complex V and complex I. This inhibition is lifted by the action of mTORC1 which inhibits 4E-BP proteins from binding their targets [108] [109]. "
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