Alkylative damage of mRNA leads to ribosome stalling and rescue by trans translation in bacteria

  1. Erica N Thomas
  2. Kyusik Q Kim
  3. Emily P McHugh
  4. Thomas Marcinkiewicz
  5. Hani S Zaher  Is a corresponding author
  1. Washington University in St Louis, United States

Abstract

Similar to DNA replication, translation of the genetic code by the ribosome is hypothesized to be exceptionally sensitive to small chemical changes to its template mRNA. Here we show that addition of common alkylating agents to growing cultures of E. coli leads to accumulation of several adducts within RNA, including N(1)-methyladenosine (m1A). As expected, the introduction of m1A to model mRNAs was found to reduce the rate of peptide-bond formation by three orders of magnitude in a well-defined in vitro system. These observations suggest that alkylative stress is likely to stall translation in vivo and necessitates activation of ribosome-rescue pathways. Indeed, the addition of alkylation agents was found to robustly activate the transfer-messenger RNA system, even when transcription was inhibited. Our findings suggest that bacteria carefully monitor the chemical integrity of their mRNA and they evolved rescue pathways to cope with its effect on translation.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Erica N Thomas

    Biology, Washington University in St Louis, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Kyusik Q Kim

    Biology, Washington University in St Louis, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Emily P McHugh

    Biology, Washington University in St Louis, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Thomas Marcinkiewicz

    Biology, Washington University in St Louis, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Hani S Zaher

    Biology, Washington University in St Louis, St. Louis, United States
    For correspondence
    hzaher@wustl.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7424-3617

Funding

National Institutes of Health (R01GM112641)

  • Hani S Zaher

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Thomas E Dever, National Institutes of Health, United States

Version history

  1. Received: August 11, 2020
  2. Accepted: September 16, 2020
  3. Accepted Manuscript published: September 17, 2020 (version 1)
  4. Version of Record published: September 28, 2020 (version 2)

Copyright

© 2020, Thomas et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Erica N Thomas
  2. Kyusik Q Kim
  3. Emily P McHugh
  4. Thomas Marcinkiewicz
  5. Hani S Zaher
(2020)
Alkylative damage of mRNA leads to ribosome stalling and rescue by trans translation in bacteria
eLife 9:e61984.
https://doi.org/10.7554/eLife.61984

Share this article

https://doi.org/10.7554/eLife.61984

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