Reconstitution of selective HIV-1 RNA packaging in vitro by membrane-bound Gag assemblies
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.
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Reviewing Editor
- Wesley I Sundquist, University of Utah, United States
Version history
- Received: January 23, 2016
- Accepted: June 24, 2016
- Accepted Manuscript published: June 25, 2016 (version 1)
- 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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