Abstract

Uncoating of the metastable HIV-1 capsid is a tightly regulated disassembly process required for release of the viral cDNA prior to nuclear import. To understand the intrinsic capsid disassembly pathway and how it can be modulated, we have developed a single-particle fluorescence microscopy method to follow the real-time uncoating kinetics of authentic HIV capsids in vitro immediately after permeabilizing the viral membrane. Opening of the first defect in the lattice is the rate-limiting step of uncoating, which is followed by rapid, catastrophic collapse. The capsid-binding inhibitor PF74 accelerates capsid opening but stabilizes the remaining lattice. In contrast, binding of a polyanion to a conserved arginine cluster in the lattice strongly delays initiation of uncoating but does not prevent subsequent lattice disassembly. Our observations suggest that different stages of uncoating can be controlled independently with the interplay between different capsid-binding regulators likely to determine the overall uncoating kinetics.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Chantal L Márquez

    EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  2. Derrick Lau

    EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  3. James Walsh

    EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  4. Vaibhav Shah

    EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  5. Conall McGuinness

    EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  6. Andrew Wong

    The Kirby Institute, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  7. Anupriya Aggarwal

    The Kirby Institute, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  8. Michael W Parker

    Australian Cancer Research Foundation Rational Drug Discovery Centre, St Vincent's Institute, Fitzroy, Australia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3101-1138
  9. David A Jacques

    EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6426-4510
  10. Stuart Turville

    The Kirby Institute, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  11. Till Böcking

    EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney, Australia
    For correspondence
    till.boecking@unsw.edu.au
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1165-3122

Funding

National Health and Medical Research Council (APP110071)

  • Stuart Turville
  • Till Böcking

Australian Centre for HIV and Hepatitis Virology Research

  • Till Böcking

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

Copyright

© 2018, Márquez 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. Chantal L Márquez
  2. Derrick Lau
  3. James Walsh
  4. Vaibhav Shah
  5. Conall McGuinness
  6. Andrew Wong
  7. Anupriya Aggarwal
  8. Michael W Parker
  9. David A Jacques
  10. Stuart Turville
  11. Till Böcking
(2018)
Kinetics of HIV-1 capsid uncoating revealed by single-molecule analysis
eLife 7:e34772.
https://doi.org/10.7554/eLife.34772

Share this article

https://doi.org/10.7554/eLife.34772

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