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5-methylcytosine modification of an Epstein-Barr virus noncoding RNA decreases its stability.

ABSTRACT: Many cellular noncoding RNAs contain chemically modified nucleotides that are essential for their function. The Epstein-Barr virus expresses two highly abundant noncoding RNAs called EBV-encoded RNA 1 (EBER1) and EBER2. To examine whether these viral RNAs contain modified nucleotides, we purified native EBERs from EBV-infected cells and performed mass spectrometry analysis. While EBER2 contains no modified nucleotides at stoichiometric amounts, EBER1 was found to carry 5-methylcytosine (m⁵C) modification. Bisulfite sequencing indicated that a single cytosine of EBER1 is methylated in ∼95% of molecules, and the RNA methyltransferase NSUN2 was identified as the EBER1-specific writer. Intriguingly, ablation of NSUN2 and thus loss of m⁵C modification resulted in an increase in EBER1 levels. We further found that EBER1 is a substrate for the RNase Angiogenin and cleavage in vivo is dependent on the presence of m⁵C, providing an explanation as to why loss of m⁵C increases EBER1 levels. Taken together, our observations indicate that m⁵C, a modification previously shown for tRNAs to oppose Angiogenin-mediated degradation, can also adversely affect RNA stability.

SUBMITTER: Henry BA

PROVIDER: S-EPMC7373997 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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5-methylcytosine modification of an Epstein-Barr virus noncoding RNA decreases its stability.

Henry Belle A BA Kanarek Jack P JP Kotter Annika A Helm Mark M Lee Nara N

RNA (New York, N.Y.) 20200430 8

Many cellular noncoding RNAs contain chemically modified nucleotides that are essential for their function. The Epstein-Barr virus expresses two highly abundant noncoding RNAs called EBV-encoded RNA 1 (EBER1) and EBER2. To examine whether these viral RNAs contain modified nucleotides, we purified native EBERs from EBV-infected cells and performed mass spectrometry analysis. While EBER2 contains no modified nucleotides at stoichiometric amounts, EBER1 was found to carry 5-methylcytosine (m<sup>5< ...[more]

PMID: 32354721

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5-methylcytosine modification of an Epstein-Barr virus noncoding RNA decreases its stability.

Publications

5-methylcytosine modification of an Epstein-Barr virus noncoding RNA decreases its stability.

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