1. Evolutionary Biology
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RNA chaperones buffer deleterious mutations in E. coli

  1. Marina Rudan
  2. Dominique Schneider
  3. Tobias Warnecke  Is a corresponding author
  4. Anita Krisko
  1. Mediterranean Institute for Life Sciences, Croatia
  2. Université Grenoble Alpes, France
  3. Imperial College, United Kingdom
Research Article
  • Cited 8
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Cite this article as: eLife 2015;4:e04745 doi: 10.7554/eLife.04745


Both proteins and RNAs can misfold into non-functional conformations. Protein chaperones promote native folding of nascent polypeptides and re-folding of misfolded species, thereby buffering mutations that compromise protein structure and function. Here we show that RNA chaperones can also act as mutation buffers that enhance organismal fitness. Using competition assays, we demonstrate that overexpression of select RNA chaperones, including three DEAD box RNA helicases (CsdA, SrmB, RhlB) and the cold shock protein CspA, improves fitness of two independently evolved E. coli mutator strains that have accumulated deleterious mutations during short- and long-term laboratory evolution. We identify strain-specific mutations that are deleterious and subject to buffering when introduced individually into the ancestral genotype. For DEAD box RNA helicases we show that buffering requires helicase activity, implicating RNA structural remodelling in the buffering process. Our results suggest that RNA chaperones might play a fundamental role in RNA evolution and evolvability.

Article and author information

Author details

  1. Marina Rudan

    Mediterranean Institute for Life Sciences, Split, Croatia
    Competing interests
    The authors declare that no competing interests exist.
  2. Dominique Schneider

    Laboratoire Adaptation et Pathogénie des Microorganismes, Université Grenoble Alpes, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Tobias Warnecke

    Molecular Systems Group, MRC Clinical Sciences Centre, Imperial College, London, United Kingdom
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
  4. Anita Krisko

    Mediterranean Institute for Life Sciences, Split, Croatia
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Naama Barkai, Weizmann Institute of Science, Israel

Publication history

  1. Received: September 14, 2014
  2. Accepted: March 24, 2015
  3. Accepted Manuscript published: March 25, 2015 (version 1)
  4. Version of Record published: April 20, 2015 (version 2)


© 2015, Rudan 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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