Binding mechanism of the matrix domain of HIV-1 Gag to lipid membranes
Abstract
Specific protein-lipid interactions are critical for viral assembly. We present a molecular dynamics simulation study on the binding mechanism of the membrane targeting domain of HIV-1 Gag protein. The matrix (MA) domain drives Gag onto the plasma membrane through electrostatic interactions at its highly-basic-region (HBR), located near the myristoylated (Myr) N-terminus of the protein. Our study suggests Myr insertion is involved in the sorting of membrane lipids around the protein binding site to prepare it for viral assembly. Our realistic membrane models confirm interactions with PIP2 and PS lipids are highly favored around the HBR, and are strong enough to keep the protein bound even without Myr insertion. We characterized Myr insertion events from microsecond trajectories, and examined the membrane response upon initial membrane targeting by MA. Insertion events only occur with one of the membrane models, showing a combination of surface charge and internal membrane structure modulate this process.
Data availability
The simulation trajectories used for the analysis presented in this work are available at the Pittsburgh Supercomputing Center (PSC) Database for simulations run on the Anton2 Machine (http://psc.edu/anton-project-summaries?id=3071&pid=34).
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All-atom molecular dynamics simulations of the matrix domain of HIV-1 Gag protein and model membranesPittsburgh Supercomputing Center Public Repository.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (R01GM063796)
- Viviana Monje-Galvan
- Gregory A Voth
National Institutes of Health (R01GM116961)
- Gregory A Voth
National Science Foundation (ACI-1548562)
- Gregory A Voth
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Monje-Galvan & Voth
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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Further reading
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