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Mammalian NSUN2 introduces 5-methylcytidines into mitochondrial tRNAs.

ABSTRACT: Post-transcriptional modifications in mitochondrial tRNAs (mt-tRNAs) play critical roles in mitochondrial protein synthesis, which produces respiratory chain complexes. In this study, we took advantage of mass spectrometric analysis to map 5-methylcytidine (m5C) at positions 48-50 in eight mouse and six human mt-tRNAs. We also confirmed the absence of m5C in mt-tRNAs isolated from Nsun2 knockout (KO) mice, as well as from NSUN2 KO human culture cells. In addition, we successfully reconstituted m5C at positions 48-50 of mt-tRNA in vitro with NSUN2 protein in the presence of S-adenosylmethionine. Although NSUN2 is predominantly localized to the nucleus and introduces m5C into cytoplasmic tRNAs and mRNAs, structured illumination microscopy clearly revealed NSUN2 foci inside mitochondria. These observations provide novel insights into the role of NSUN2 in the physiology and pathology of mitochondrial functions.

SUBMITTER: Shinoda S

PROVIDER: S-EPMC6895283 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Mammalian NSUN2 introduces 5-methylcytidines into mitochondrial tRNAs.

Shinoda Saori S Kitagawa Sho S Nakagawa Shinichi S Wei Fan-Yan FY Tomizawa Kazuhito K Araki Kimi K Araki Masatake M Suzuki Takeo T Suzuki Tsutomu T

Nucleic acids research 20190901 16

Post-transcriptional modifications in mitochondrial tRNAs (mt-tRNAs) play critical roles in mitochondrial protein synthesis, which produces respiratory chain complexes. In this study, we took advantage of mass spectrometric analysis to map 5-methylcytidine (m5C) at positions 48-50 in eight mouse and six human mt-tRNAs. We also confirmed the absence of m5C in mt-tRNAs isolated from Nsun2 knockout (KO) mice, as well as from NSUN2 KO human culture cells. In addition, we successfully reconstituted m ...[more]

PMID: 31287866

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NSUN2 introduces 5-methylcytosines in mammalian mitochondrial tRNAs.

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NSUN2 introduces 5-methylcytosines in mammalian mitochondrial tRNAs

Project description:We show that NSUN2 in necessary for the generation of m5C at positions 48, 49 and 50 of several mammalian mitochondrial tRNAs

2019-06-19 | GSE132020 | GEO

NSUN2 introduces 5-methylcytosines in mammalian mitochondrial tRNAs

Project description:NSUN2 introduces 5-methylcytosines in mammalian mitochondrial tRNAs

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