Reconstitution of selective HIV-1 RNA packaging in vitro by membrane-bound Gag assemblies

  1. Lars-Anders Carlson
  2. Yun Bai
  3. Sarah C Keane
  4. Jennifer A Doudna
  5. James H Hurley  Is a corresponding author
  1. University of California, Berkeley, United States
  2. ShanghaiTech University, China
  3. Howard Hughes Medical Institute, University of California, Berkeley, United States

Abstract

HIV-1 Gag selects and packages a dimeric, unspliced viral RNA in the context of a large excess of cytosolic human RNAs. As Gag assembles on the plasma membrane, the HIV-1 genome is enriched relative to cellular RNAs by an unknown mechanism. We used a minimal system consisting of purified RNAs, recombinant HIV-1 Gag and giant unilamellar vesicles to recapitulate the selective packaging of the 5' untranslated region of the HIV-1 genome in the presence of excess competitor RNA. Mutations in the CA-CTD domain of Gag which subtly affect the self-assembly of Gag abrogated RNA selectivity. We further found that tRNA suppresses Gag membrane binding less when Gag has bound viral RNA. The ability of HIV-1 Gag to selectively package its RNA genome and its self-assembly on membranes are thus interdependent on one another.

Article and author information

Author details

  1. Lars-Anders Carlson

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Yun Bai

    School of Life Science and Technology, ShanghaiTech University, Shanghai, China
    Competing interests
    The authors declare that no competing interests exist.
  3. Sarah C Keane

    Howard Hughes Medical Institute, University of California, Berkeley, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Jennifer A Doudna

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. James H Hurley

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    jimhurley@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

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

Publication history

  1. Received: January 23, 2016
  2. Accepted: June 24, 2016
  3. Accepted Manuscript published: June 25, 2016 (version 1)
  4. Version of Record published: July 15, 2016 (version 2)

Copyright

© 2016, Carlson 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. Lars-Anders Carlson
  2. Yun Bai
  3. Sarah C Keane
  4. Jennifer A Doudna
  5. James H Hurley
(2016)
Reconstitution of selective HIV-1 RNA packaging in vitro by membrane-bound Gag assemblies
eLife 5:e14663.
https://doi.org/10.7554/eLife.14663
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