Gene network analysis identifies a central post-transcriptional regulator of cellular stress survival

  1. Matthew Tien
  2. Aretha Fiebig
  3. Sean Crosson  Is a corresponding author
  1. University of Chicago, United States

Abstract

Cells adapt to shifts in their environment by remodeling transcription. Measuring changes in transcription at the genome scale is now routine, but defining the functional significance of individual genes within large gene expression datasets remains a major challenge. We applied a network-based algorithm to interrogate publicly available gene expression data to predict genes that serve major functional roles in Caulobacter crescentus stress survival. This approach identified GsrN, a conserved small RNA that is directly activated by the general stress sigma factor, σT, and functions as a potent post-transcriptional regulator of survival across distinct conditions including osmotic and oxidative stress. Under hydrogen peroxide stress, GsrN protects cells by base pairing with the leader of katG mRNA and activating expression of KatG catalase/peroxidase protein. We conclude that GsrN convenes a post-transcriptional layer of gene expression that serves a central functional role in Caulobacter stress physiology.

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The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Matthew Tien

    Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0006-9644
  2. Aretha Fiebig

    Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Sean Crosson

    Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, United States
    For correspondence
    scrosson@uchicago.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1727-322X

Funding

National Institutes of Health (1R01GM087353)

  • Sean Crosson

National Institutes of Health (U19AI107792)

  • Sean Crosson

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

Reviewing Editor

  1. Michael T Laub, Massachusetts Institute of Technology, United States

Version history

  1. Received: November 18, 2017
  2. Accepted: March 13, 2018
  3. Accepted Manuscript published: March 14, 2018 (version 1)
  4. Version of Record published: March 26, 2018 (version 2)

Copyright

© 2018, Tien 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. Matthew Tien
  2. Aretha Fiebig
  3. Sean Crosson
(2018)
Gene network analysis identifies a central post-transcriptional regulator of cellular stress survival
eLife 7:e33684.
https://doi.org/10.7554/eLife.33684

Share this article

https://doi.org/10.7554/eLife.33684

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