Abstract
Assembly of HIV-1 viral particles is a critical step of the HIV-1 life cycle; yet many details of this complex process are unknown. The Gag polyprotein drives viral particle assembly at the plasma membrane via three different types of interactions: protein-protein, protein-RNA, and protein-membrane interactions. As an approach to tease apart the importance of these interactions during viral particle assembly, in particular at the step of Gag membrane binding, we have developed an in vitro liposome-binding assay. Below we describe how to prepare liposomes, which serve as model membranes, and how to assess their interaction with Gag by liposome flotation centrifugation. Additionally, we outline extensions of this basic assay that can be used to address the role of RNA in regulating Gag-membrane interactions.
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Acknowledgments
We would like to thank the past and present members of our laboratory for their contributions to development of the methods described here. The methods described here were developed in the studies supported by the National Institutes of Health grant R01 AI071727 (to A.O.).
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Todd, G.C., Ono, A. (2016). Methods to Study Determinants for Membrane Targeting of HIV-1 Gag In Vitro. In: Prasad, V., Kalpana, G. (eds) HIV Protocols. Methods in Molecular Biology, vol 1354. Humana Press, New York, NY. https://doi.org/10.1007/978-1-4939-3046-3_12
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DOI: https://doi.org/10.1007/978-1-4939-3046-3_12
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