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bioRxiv · 10.1101/2022.03.21.485107

The S. cerevisiae m6A-reader Pho92 impacts meiotic recombination by controlling key methylated transcripts

Abstract

N6-methyladenosine (m6A), the most abundant internal modification of eukaryotic mRNAs, participates in the post-transcriptional control of gene expression. In Saccharomyces cerevisiae, m6A is only found during meiosis. Although the deletion of the m6A- methyltransferase Ime4 impairs this process, the molecular impact of m6A on gene expression remains ill defined. Here we investigated the function of the budding yeast m6A reader Pho92. We found that Pho92 is specifically expressed during meiosis and impacts meiotic progression. We used high-throughput RNA sequencing and mapping of Pho92-binding sites following UV-crosslinking to show that Pho92 is recruited to specific mRNAs in an m6A-dependent manner during the meiotic prophase, preceding their down-regulation. Strikingly, point mutations altering m6A sites in mRNAs targeted by Pho92 are sufficient to delay their down-regulation and, in one case, to impact meiotic progression. Altogether, our results indicate that Pho92 facilitate the meiotic progression by accelerating the down-regulation of timely-regulated mRNAs during meiotic recombination.

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BibTeXRIS

Scutenaire, J., Plassard, D., Matelot, M., Villa, T., Zumsteg, J., Libri, D., Seraphin, B.. 2022-03-21. The S. cerevisiae m6A-reader Pho92 impacts meiotic recombination by controlling key methylated transcripts. https://doi.org/10.1101/2022.03.21.485107

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