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bioRxiv · 10.1101/2020.02.10.941153

mRNA secondary structure stability regulates bacterial translation insulation and re-initiation

Chemla, Y.·Peeri, M.·Heltberg, M. L.·Eichler, J.·Jensen, M. H.·Tuller, T.·Alfonta, L.
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Abstract

In bacteria, translation re-initiation is crucial for synthesizing proteins encoded by genes that are organized into operons. The mechanisms regulating translation re-initiation remain, however, poorly understood. We now describe the ribosome termination structure (RTS), a conserved and stable mRNA secondary structure precisely localized downstream of stop codons, which serves as the main factor governing re-initiation efficiency in a synthetic Escherichia coli operon. We further report that in 95% of 128 analyzed bacterial genomes representing all phyla, this structure is selectively depleted when re-initiation is advantageous yet selectively enriched so as to insulate translation when re-initiation is deleterious.

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Chemla, Y., Peeri, M., Heltberg, M. L., Eichler, J., Jensen, M. H., Tuller, T., Alfonta, L.. 2020-02-10. mRNA secondary structure stability regulates bacterial translation insulation and re-initiation. https://doi.org/10.1101/2020.02.10.941153

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