Abstract

The principal structural component of a retrovirus particle is the Gag protein. Retroviral genomic RNAs contain a 'packaging signal' ('Ψ') and are packaged in virus particles with very high selectivity. However, if no genomic RNA is present, Gag assembles into particles containing cellular mRNA molecules. The mechanism by which genomic RNA is normally selected during virus assembly is not understood. We previously reported (Comas-Garcia et al., 2017) that at physiological ionic strength, recombinant HIV-1 Gag binds with similar affinities to RNAs with or without Ψ, and proposed that genomic RNA is selectively packaged because binding to Ψ initiates particle assembly more efficiently than other RNAs. We now present data directly supporting this hypothesis. We also show that one or more short stretches of unpaired G residues are important elements of Ψ; Ψ may not be localized to a single structural element, but is probably distributed over >100 bases.

Data availability

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

Article and author information

Author details

  1. Mauricio Comas-Garcia

    HIV Dynamics and Replication Program, National Cancer Institute, Frederick, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7733-5138
  2. Tomas Kroupa

    HIV Dynamics and Replication Program, National Cancer Institute, Frederick, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5996-9057
  3. Siddhartha AK Datta

    HIV Dynamics and Replication Program, National Cancer Institute, Frederick, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Demetria P Harvin

    HIV Dynamics and Replication Program, National Cancer Institute, Frederick, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Wei-Shau Hu

    HIV Dynamics and Replication Program, National Cancer Institute, Frederick, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Alan Rein

    HIV Dynamics and Replication Program, National Cancer Institute, Frederick, United States
    For correspondence
    reina@mail.nih.gov
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8273-546X

Funding

National Cancer Institute

  • Mauricio Comas-Garcia
  • Tomas Kroupa
  • Siddhartha AK Datta
  • Demetria P Harvin
  • Wei-Shau Hu
  • Alan Rein

Intramural AIDS Targeted Antiviral Therapy Program

  • Mauricio Comas-Garcia
  • Alan Rein

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

Reviewing Editor

  1. Stephen P Goff, Howard Hughes Medical Institute, Columbia University, United States

Version history

  1. Received: May 21, 2018
  2. Accepted: August 1, 2018
  3. Accepted Manuscript published: August 2, 2018 (version 1)
  4. Version of Record published: August 14, 2018 (version 2)

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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  1. Mauricio Comas-Garcia
  2. Tomas Kroupa
  3. Siddhartha AK Datta
  4. Demetria P Harvin
  5. Wei-Shau Hu
  6. Alan Rein
(2018)
Efficient support of virus-like particle assembly by the HIV-1 packaging signal
eLife 7:e38438.
https://doi.org/10.7554/eLife.38438

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https://doi.org/10.7554/eLife.38438

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