1. Structural Biology and Molecular Biophysics
  2. Cell Biology
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A structural model of the active ribosome-bound membrane protein insertase YidC

  1. Stephan Wickles
  2. Abhishek Singharoy
  3. Jessica Andreani
  4. Stefan Seemayer
  5. Lukas Bischoff
  6. Otto Berninghausen
  7. Johannes Soeding
  8. Klaus Schulten
  9. Eli O van der Sluis
  10. Roland Beckmann  Is a corresponding author
  1. Ludwig-Maximilians-Universität München, Germany
  2. University of Illinois at Urbana-Champaign, United States
  3. University of Illinois at Urbana-Champagin, United States
Research Article
  • Cited 39
  • Views 3,522
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Cite this article as: eLife 2014;3:e03035 doi: 10.7554/eLife.03035

Abstract

The integration of most membrane proteins into the cytoplasmic membrane of bacteria occurs co-translationally. The universally conserved YidC protein mediates this process either individually as a membrane protein insertase, or in concert with the SecY complex. Here, we present a structural model of YidC based on evolutionary co-variation analysis, lipid-versus-protein-exposure and molecular dynamics simulations. The model suggests a distinctive arrangement of the conserved five transmembrane domains and a helical hairpin between transmembrane segment 2 (TM2) and TM3 on the cytoplasmic membrane surface. The model was used for docking into a cryo-electron microscopy reconstruction of a translating YidC-ribosome complex carrying the YidC substrate FOc. This structure reveals how a single copy of YidC interacts with the ribosome at the ribosomal tunnel exit and identifies a site for membrane protein insertion at the YidC protein-lipid interface. Together, these data suggest a mechanism for the co-translational mode of YidC-mediated membrane protein insertion.

Article and author information

Author details

  1. Stephan Wickles

    Ludwig-Maximilians-Universität München, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Abhishek Singharoy

    University of Illinois at Urbana-Champaign, Urbana, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jessica Andreani

    Ludwig-Maximilians-Universität München, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Stefan Seemayer

    Ludwig-Maximilians-Universität München, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Lukas Bischoff

    Ludwig-Maximilians-Universität München, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Otto Berninghausen

    Ludwig-Maximilians-Universität München, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.
  7. Johannes Soeding

    Ludwig-Maximilians-Universität München, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.
  8. Klaus Schulten

    University of Illinois at Urbana-Champagin, Urbana, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Eli O van der Sluis

    Ludwig-Maximilians-Universität München, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.
  10. Roland Beckmann

    Ludwig-Maximilians-Universität München, Munich, Germany
    For correspondence
    beckmann@lmb.uni-muenchen.de
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Ramanujan S Hegde, MRC Laboratory of Molecular Biology, United Kingdom

Publication history

  1. Received: April 8, 2014
  2. Accepted: July 8, 2014
  3. Accepted Manuscript published: July 10, 2014 (version 1)
  4. Version of Record published: August 7, 2014 (version 2)

Copyright

© 2014, Wickles 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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