RNase III-mediated processing of a trans-acting bacterial sRNA and its cis-encoded antagonist

  1. Sarah Lauren Svensson
  2. Cynthia Mira Sharma  Is a corresponding author
  1. University of Würzburg, Germany

Abstract

Bacterial small RNAs (sRNAs) are important post-transcriptional regulators in stress responses and virulence. They can be derived from an expanding list of genomic contexts, such as processing from parental transcripts by RNase E. The role of RNase III in sRNA biogenesis is less well understood despite its well-known roles in rRNA processing, RNA decay, and cleavage of sRNA-mRNA duplexes. Here, we show that RNase III processes a pair of cis-encoded sRNAs (CJnc190 and CJnc180) of the foodborne pathogen Campylobacter jejuni. While CJnc180 processing by RNase III requires CJnc190, In contrast, RNase III processes CJnc190 independent of CJnc180 via cleavage of an intramolecular duplex. We also show that CJnc190 directly represses translation of the colonization factor PtmG by targeting a G-rich ribosome binding site, and uncover that CJnc180 is a cis-acting antagonist of CJnc190, indirectly affecting ptmG regulation. Our study highlights a role for RNase III in sRNA biogenesis and adds cis-encoded RNAs to the expanding diversity of transcripts that antagonize bacterial sRNAs.

Data availability

All data generated or analysed during this study are included in the manuscript or are provided as supporting data files (e.g., gel images).

The following previously published data sets were used

Article and author information

Author details

  1. Sarah Lauren Svensson

    Department of Molecular Infection Biology II, Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Cynthia Mira Sharma

    Department of Molecular Infection Biology II, Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany
    For correspondence
    cynthia.sharma@uni-wuerzburg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2321-9705

Funding

Bavarian Research Network

  • Cynthia Mira Sharma

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

Reviewing Editor

  1. Lydia Contreras, The University of Texas at Austin, United States

Publication history

  1. Received: April 2, 2021
  2. Accepted: November 28, 2021
  3. Accepted Manuscript published: November 29, 2021 (version 1)
  4. Version of Record published: December 20, 2021 (version 2)

Copyright

© 2021, Svensson & Sharma

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. Sarah Lauren Svensson
  2. Cynthia Mira Sharma
(2021)
RNase III-mediated processing of a trans-acting bacterial sRNA and its cis-encoded antagonist
eLife 10:e69064.
https://doi.org/10.7554/eLife.69064

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