mRNA-programmed translation pauses in the targeting of E. coli membrane proteins

  1. Nir Fluman
  2. Sivan Navon
  3. Eitan Bibi
  4. Yitzhak Pilpel  Is a corresponding author
  1. Weizmann Institute of Science, Israel

Abstract

In all living organisms, ribosomes translating membrane proteins are targeted to membrane translocons early in translation, by the ubiquitous Signal Recognition Particle (SRP) system. In eukaryotes, the SRP Alu domain arrests translation elongation of membrane proteins until targeting is complete. Curiously however, the Alu domain is lacking in most eubacteria. Here, by analyzing genome-wide data on translation rates, we identified a potential compensatory mechanism in E. coli that serves to slow down translation during membrane protein targeting. The underlying mechanism is likely programmed into the coding sequence, where Shine-Dalgarno-like elements trigger elongation pauses at strategic positions during early stages of translation. We provide experimental evidence that slow translation during targeting improves membrane protein production fidelity, as it correlates with better folding of overexpressed membrane proteins. Thus, slow elongation is important for membrane protein targeting in E. coli, which utilizes mechanisms different from the eukaryotic one to control translation speed.

Article and author information

Author details

  1. Nir Fluman

    Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.
  2. Sivan Navon

    Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.
  3. Eitan Bibi

    Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.
  4. Yitzhak Pilpel

    Weizmann Institute of Science, Rehovot, Israel
    For correspondence
    Pilpel@weizmann.ac.il
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Nahum Sonenberg, McGill University, Canada

Publication history

  1. Received: May 21, 2014
  2. Accepted: August 16, 2014
  3. Accepted Manuscript published: August 18, 2014 (version 1)
  4. Version of Record published: September 23, 2014 (version 2)

Copyright

© 2014, Fluman 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. Nir Fluman
  2. Sivan Navon
  3. Eitan Bibi
  4. Yitzhak Pilpel
(2014)
mRNA-programmed translation pauses in the targeting of E. coli membrane proteins
eLife 3:e03440.
https://doi.org/10.7554/eLife.03440

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