A bifunctional snoRNA with separable activities in guiding rRNA 2'-O-methylation and scaffolding gametogenesis effectors

Leroy, E.; Challal, D.; Pelletier, S.; Goncalves, C.; Menant, A.; Marchand, V.; Jaszczyszyn, Y.; van Dijk, E.; Naquin, D.; Andreani, J.; Motorin, Y.; PALANCADE, B.; Rougemaille, M.

doi:10.1101/2024.10.03.615557

bioRxiv · 10.1101/2024.10.03.615557

A bifunctional snoRNA with separable activities in guiding rRNA 2'-O-methylation and scaffolding gametogenesis effectors

Leroy, E.·Challal, D.·Pelletier, S.·Goncalves, C.·Menant, A.·Marchand, V.·Jaszczyszyn, Y.·van Dijk, E.·Naquin, D.·Andreani, J.·Motorin, Y.·PALANCADE, B.·Rougemaille, M.

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Abstract

Small nucleolar RNAs are non-coding transcripts that guide chemical modifications of RNA substrates and modulate gene expression at the epigenetic and post-transcriptional levels. However, the extent of their regulatory potential and the underlying molecular mechanisms remain poorly understood. Here, we identify a conserved, previously unannotated intronic C/D-box snoRNA, termed snR107, hosted in the fission yeast long non-coding RNA mamRNA and carrying two independent cellular functions. On the one hand, snR107 guides site-specific 25S rRNA 2-O-methylation and promotes pre-rRNA processing and 60S subunit biogenesis. On the other hand, snR107 associates with the gametogenic RNA-binding proteins Mmi1 and Mei2, mediating their reciprocal inhibition and restricting meiotic gene expression during sexual differentiation. Both functions require distinct cis-motifs within snR107, including a conserved 2-O-methylation guiding sequence. Together, our results position snR107 as a dual regulator of rRNA modification and gametogenesis effectors, expanding our vision on the non-canonical functions exerted by snoRNAs in cell fate decisions.

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Leroy, E., Challal, D., Pelletier, S., Goncalves, C., Menant, A., Marchand, V., Jaszczyszyn, Y., van Dijk, E., Naquin, D., Andreani, J., Motorin, Y., PALANCADE, B., Rougemaille, M.. 2024-10-03. A bifunctional snoRNA with separable activities in guiding rRNA 2'-O-methylation and scaffolding gametogenesis effectors. https://doi.org/10.1101/2024.10.03.615557

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