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bioRxiv · 10.1101/2024.11.26.625382

Unconventional mRNA processing and degradation pathways for the polycistronic yrzI mRNA in B. subtilis

GILET, l.·Leroy, M.·Maes, A.·CONDON, c.·BRAUN, f.
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Abstract

The ribosome-associated endoribonuclease Rae1 cleaves the Bacillus subtilis yrzI operon mRNA in a translation-dependent manner. This operon encodes up to four small peptides, S1027, YrzI, S1025 and S1024, whose functions were unknown. We show that YrzI is toxic at high concentrations, but co-expression with S1025 abolishes its toxicity. We show that a highly stable mRNA species containing the YrzI and S1025 open reading frames results from endoribonucleolytic cleavage upstream of the yrzI ORF followed by 5-exoribonucleolytic processing arrested by ribosomes bound to its exceptionally strong Shine-Dalgarno sequence. Degradation of this mRNA requires either translation-dependent cleavage within S1025 by Rae1 or direct attack from the structured 3-end by 3-exoribonucleases. Both pathways are atypical for a B. subtilis mRNA.

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GILET, l., Leroy, M., Maes, A., CONDON, c., BRAUN, f.. 2024-11-26. Unconventional mRNA processing and degradation pathways for the polycistronic yrzI mRNA in B. subtilis. https://doi.org/10.1101/2024.11.26.625382

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