ATP-induced asymmetric pre-protein folding as a driver of protein translocation through the Sec machinery

  1. Robin A Corey
  2. Zainab Ahdash
  3. Anokhi Shah
  4. Euan Pyle
  5. William John Allen
  6. Tomas Fessl
  7. Janet E Lovett  Is a corresponding author
  8. Argyris Politis  Is a corresponding author
  9. Ian Collinson  Is a corresponding author
  1. University of Bristol, United Kingdom
  2. King's College London, United Kingdom
  3. University of St Andrews, United Kingdom
  4. University of South Bohemia in Ceske Budejovice, Czech Republic

Abstract

Transport of proteins across membranes is a fundamental process, achieved in every cell by the 'Sec' translocon. In prokaryotes, SecYEG associates with the motor ATPase SecA to carry out translocation for pre-protein secretion. Previously, we proposed a Brownian ratchet model for transport, whereby the free energy of ATP-turnover favours the directional diffusion of the polypeptide [Allen et al. eLife 2016]. Here, we show that ATP enhances this process by modulating secondary structure formation within the translocating protein. A combination of molecular simulation with hydrogen-deuterium-exchange mass spectrometry and electron paramagnetic resonance spectroscopy reveal an asymmetry across the membrane: ATP induced conformational changes in the cytosolic cavity promote unfolded pre-protein structure, while the exterior cavity favours its formation. This ability to exploit structure within a pre-protein is an unexplored area of protein transport, which may apply to other protein transporters, such as those of the endoplasmic reticulum and mitochondria.

Data availability

All data generated during this study are included in the Figures of the mansucript. EPR data is available at https://doi.org/10.17630/0fedaeec-7e27-4876-a6d1-cda2d3a6799c.

The following data sets were generated

Article and author information

Author details

  1. Robin A Corey

    School of Biochemistry, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1820-7993
  2. Zainab Ahdash

    Department of Chemistry, King's College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Anokhi Shah

    School of Physics and Astronomy, University of St Andrews, St Andrews, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Euan Pyle

    Department of Chemistry, King's College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4633-4917
  5. William John Allen

    School of Biochemistry, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9513-4786
  6. Tomas Fessl

    Faculty of Sciences, University of South Bohemia in Ceske Budejovice, České Budějovice, Czech Republic
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6969-4870
  7. Janet E Lovett

    School of Physics and Astronomy, University of St Andrews, St Andrews, United Kingdom
    For correspondence
    jel20@st-andrews.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
  8. Argyris Politis

    Department of Chemistry, King's College London, London, United Kingdom
    For correspondence
    argyris.politis@kcl.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6658-3224
  9. Ian Collinson

    School of Biochemistry, University of Bristol, Bristol, United Kingdom
    For correspondence
    ian.collinson@bristol.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3931-0503

Funding

Biotechnology and Biological Sciences Research Council (BB/M003604/1)

  • Robin A Corey
  • William John Allen
  • Ian Collinson

Wellcome (104632)

  • William John Allen
  • Ian Collinson

Royal Society (University Research Fellowship)

  • Janet E Lovett

Wellcome (109854/Z/15/Z)

  • Zainab Ahdash
  • Argyris Politis

Wellcome (099149/Z/12/Z)

  • Anokhi Shah
  • Janet E Lovett

European Regional Development Fund (CZ.02.1.01/0.0/0.0/15_003/0000441)

  • Tomas Fessl

Engineering and Physical Sciences Research Council (ep/m508214/1)

  • Anokhi Shah

Biotechnology and Biological Sciences Research Council (BB/I008675/1)

  • Robin A Corey
  • William John Allen
  • Ian Collinson

Biotechnology and Biological Sciences Research Council (BB/N015126/1)

  • Robin A Corey
  • William John Allen
  • Ian Collinson

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

Copyright

© 2019, Corey 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. Robin A Corey
  2. Zainab Ahdash
  3. Anokhi Shah
  4. Euan Pyle
  5. William John Allen
  6. Tomas Fessl
  7. Janet E Lovett
  8. Argyris Politis
  9. Ian Collinson
(2019)
ATP-induced asymmetric pre-protein folding as a driver of protein translocation through the Sec machinery
eLife 8:e41803.
https://doi.org/10.7554/eLife.41803

Share this article

https://doi.org/10.7554/eLife.41803

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