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Effect of QTRT2 KO on mitochondrial translation

ABSTRACT: Mitochondria are organelles that generate most of the energy in eukaryotic cells in the form of ATP via oxidative phosphorylation in eukaryote. Twenty-two species of mitochondrial (mt-)tRNAs encoded in mtDNA are required to translate essential subunits of the respiratory chain complexes involved in oxidative phosphorylation. mt-tRNAs contain post-transcriptional modifications introduced by nuclear-encoded tRNA-modifying enzymes. These modifications are required for deciphering genetic code accurately, as well as stabilizing tRNA. Loss of tRNA modifications frequently results in severe pathological consequences. We performed a comprehensive analysis of post-transcriptional modifications of all human mt-tRNAs, including 14 previously-uncharacterized species, and revised the modification status of some of the previously studied species. In total, we found 17 kinds of RNA modifications at 137 positions (8.7% in 1,575 nucleobases) in 22 species of human mt-tRNAs. An up-to-date list of 34 genes responsible for human mt-tRNA modifications are provided. We here demonstrated that both QTRT1 and QTRT2 are required for biogenesis of queuosine (Q) at position 34 of four mt-tRNAs. Our results provide insight into the molecular mechanisms underlying the mitochondrial decoding system, and could help to elucidate the molecular pathogenesis of human mitochondrial diseases caused by aberrant tRNA modifications.

ORGANISM(S): Homo sapiens

PROVIDER: GSE150439 | GEO | 2020/08/28

REPOSITORIES: GEO

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