Mitochondrial Protein Synthesis and mtDNA Levels Coordinated through an Aminoacyl-tRNA Synthetase Subunit

https://www.cell.com/cell-reports/fulltext/S2211-1247(19)30329-8?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2211124719303298%3Fshowall%3Dtrue

Picchioni D, Antolin-Fontes A, Camacho N, Schmitz C, Pons-Pons A, Rodríguez-Escribà M, Machallekidou A, Güler MN, Siatra P, Carretero-Junquera M, Serrano A, Hovde SL, Knobel PA, Novoa EM, Solà-Vilarrubias M, Kaguni LS, Stracker TH, Ribas de Pouplana L

• The authors investigate a signalling pathway which couples mtDNA translation to mtDNA copy number 
• They identify a protein (SLIMP) which is essential for mitochondrial respiration, and is involved in tRNA-serine aminoacylation
• SLIMP interacts with the protein LON, which degrades TFAM. TFAM is a protein involved in forming mtDNA-protein complexes known as nucleoids. Reduction in TFAM levels is associated with mtDNA depletion.
• Hence mitochondrial translation is directly coupled to mtDNA copy number.