First Author | Arguello T | Year | 2018 |
Journal | J Biol Chem | Volume | 293 |
Issue | 39 | Pages | 15021-15032 |
PubMed ID | 30087118 | Mgi Jnum | J:270266 |
Mgi Id | MGI:6268476 | Doi | 10.1074/jbc.RA118.003838 |
Citation | Arguello T, et al. (2018) Mitochondrial methionyl N-formylation affects steady-state levels of oxidative phosphorylation complexes and their organization into supercomplexes. J Biol Chem 293(39):15021-15032 |
abstractText | N-Formylation of the Met-tRNA(Met) by the nuclearly encoded mitochondrial methionyl-tRNA formyltransferase (MTFMT) has been found to be a key determinant of protein synthesis initiation in mitochondria. In humans, mutations in the MTFMT gene result in Leigh syndrome, a progressive and severe neurometabolic disorder. However, the absolute requirement of formylation of Met-tRNA(Met) for protein synthesis in mammalian mitochondria is still debated. Here, we generated a Mtfmt-KO mouse fibroblast cell line and demonstrated that N-formylation of the first methionine via fMet-tRNA(Met) by MTFMT is not an absolute requirement for initiation of protein synthesis. However, it differentially affected the efficiency of synthesis of mtDNA-coded polypeptides. Lack of methionine N-formylation did not compromise the stability of these individual subunits but had a marked effect on the assembly and stability of the OXPHOS complexes I and IV and on their supercomplexes. In summary, N-formylation is not essential for mitochondrial protein synthesis but is critical for efficient synthesis of several mitochondrially encoded peptides and for OXPHOS complex stability and assembly into supercomplexes. |