1. Cell Biology
  2. Microbiology and Infectious Disease
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Synchronized HIV assembly by tunable PIP2 changes reveals PIP2 requirement for stable Gag anchoring

  1. Frauke Mücksch
  2. Vibor Laketa
  3. Barbara Müller
  4. Carsten Schultz
  5. Hans-Georg Kräusslich  Is a corresponding author
  1. University Hospital Heidelberg, Germany
  2. European Molecular Biology Laboratory, Germany
Research Article
  • Cited 19
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Cite this article as: eLife 2017;6:e25287 doi: 10.7554/eLife.25287

Abstract

HIV-1 assembles at the plasma membrane (PM) of infected cells. PM association of the main structural protein Gag depends on its myristoylated MA domain and PM PI(4,5)P2. Using a novel chemical biology tool that allows rapidly tunable manipulation of PI(4,5)P2 levels in living cells, we show that depletion of PI(4,5)P2 completely prevents Gag PM targeting and assembly site formation. Unexpectedly, PI(4,5)P2 depletion also caused loss of pre-assembled Gag lattices from the PM. Subsequent restoration of PM PI(4,5)P2 reinduced assembly site formation even in the absence of new protein synthesis, indicating that the dissociated Gag molecules remained assembly competent. These results reveal an important role of PI(4,5)P2 for HIV-1 morphogenesis beyond Gag recruitment to the PM and suggest a dynamic equilibrium of Gag-lipid interactions. Furthermore, they establish an experimental system that permits synchronized induction of HIV-1 assembly leading to induced production of infectious virions by targeted modulation of Gag PM targeting.

Article and author information

Author details

  1. Frauke Mücksch

    Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0132-5101
  2. Vibor Laketa

    Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
    Competing interests
    No competing interests declared.
  3. Barbara Müller

    Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5726-5585
  4. Carsten Schultz

    Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
    Competing interests
    Carsten Schultz, C. Schultz is a shareholder of the company SiChem, which distributes rCDS.
  5. Hans-Georg Kräusslich

    Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
    For correspondence
    hans-georg.kraeusslich@med.uni-heidelberg.de
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8756-329X

Funding

Deutsche Forschungsgemeinschaft (TRR 83 project 14)

  • Hans-Georg Kräusslich

Deutsche Forschungsgemeinschaft (TRR 83 project 2)

  • Carsten Schultz

Deutsche Forschungsgemeinschaft (SFB 1129 project 5)

  • Hans-Georg Kräusslich

Deutsche Forschungsgemeinschaft (SFB 1129 project 6)

  • Barbara Müller

Deutsche Forschungsgemeinschaft (Excellence Cluster CellNetworks Exc81)

  • Barbara Müller
  • Hans-Georg Kräusslich

Deutsches Zentrum für Infektionsforschung (Project 7.5 TTU HIV)

  • Hans-Georg Kräusslich

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

Reviewing Editor

  1. Wesley I Sundquist, University of Utah School of Medicine, United States

Publication history

  1. Received: January 20, 2017
  2. Accepted: May 25, 2017
  3. Accepted Manuscript published: June 2, 2017 (version 1)
  4. Version of Record published: July 3, 2017 (version 2)

Copyright

© 2017, Mücksch 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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