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C²-methyladenosine in tRNA promotes protein translation by facilitating the decoding of tandem m²A-tRNA-dependent codons.

ABSTRACT: RNA modification C²-methyladenosine (m²A) exists in both rRNA and tRNA of Escherichia coli (E. coli), installed by the methyltransferase RlmN using a radical-S-adenosylmethionine (SAM) mechanism. However, the precise function of m²A in tRNA and its ubiquity in plants have remained unclear. Here we discover the presence of m²A in chloroplast rRNA and tRNA, as well as cytosolic tRNA, in multiple plant species. We identify six m²A-modified chloroplast tRNAs and two m²A-modified cytosolic tRNAs across different plants. Furthermore, we characterize three Arabidopsis m²A methyltransferases-RLMNL1, RLMNL2, and RLMNL3-which methylate chloroplast rRNA, chloroplast tRNA, and cytosolic tRNA, respectively. Our findings demonstrate that m²A37 promotes a relaxed conformation of tRNA, enhancing translation efficiency in chloroplast and cytosol by facilitating decoding of tandem m²A-tRNA-dependent codons. This study provides insights into the molecular function and biological significance of m²A, uncovering a layer of translation regulation in plants.

SUBMITTER: Duan HC

PROVIDER: S-EPMC10838301 | biostudies-literature | 2024 Feb

REPOSITORIES: biostudies-literature

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C2-methyladenosine in tRNA promotes protein translation by facilitating the decoding of tandem m2A-tRNA-dependent codons.

Duan Hong-Chao HC Zhang Chi C Song Peizhe P Yang Junbo J Wang Ye Y Jia Guifang G

Nature communications 20240203 1

RNA modification C2-methyladenosine (m2A) exists in both rRNA and tRNA of Escherichia coli (E. coli), installed by the methyltransferase RlmN using a radical-S-adenosylmethionine (SAM) mechanism. However, the precise function of m2A in tRNA and its ubiquity in plants have remained unclear. Here we discover the presence of m2A in chloroplast rRNA and tRNA, as well as cytosolic tRNA, in multiple plant species. We identify six m2A-modified chlo ...[more]

PMID: 38310199

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C²-methyladenosine in tRNA promotes protein translation by facilitating the decoding of tandem m²A-tRNA-dependent codons.

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C<sup>2</sup>-methyladenosine in tRNA promotes protein translation by facilitating the decoding of tandem m<sup>2</sup>A-tRNA-dependent codons.

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