Related Experiment Video
Updated: Jul 23, 2025
08:21
Visualization of HIV-1 Gag Binding to Giant Unilamellar Vesicle GUV Membranes
Published on: July 28, 2016
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Early HIV-1 Gag Assembly on Lipid Membrane with vRNA.
Anne X-Z Zhou1, John A Hammond1, Kai Sheng1
1Department of Integrative Structural and Computational Biology, The Scripps Research Institute; La Jolla, CA 92037, USA.
Research Square
|July 18, 2023
Summary
HIV-1 capsid assembly begins with a trimer nucleus formation. Subsequent growth involves RNA-dependent addition of Gag monomers, supporting a lattice edge expansion model for immature capsid formation.
Area of Science:
- Virology
- Structural Biology
- Biochemistry
Background:
- HIV-1 capsid assembly is crucial for viral infection.
- The viral structural protein Gag mediates membrane association, RNA binding, and particle formation.
- Mechanisms of Gag complex nucleation and growth remain unclear.
Approach:
- Investigated HIV-1 Gag assembly using mass photometry.
- Utilized full-length myristoylated Gag, RNA, and lipids in a model membrane system.
- Recorded dynamic single-molecule data to observe assembly intermediates.
Key Points:
- Myristoylated Gag forms a trimer nucleus on model membranes.
- This nucleus selectively binds dimeric RNA with the packaging signal.
- Oligomer growth occurs via sequential addition of 1-2 Gag monomers, dependent on vRNA.
Conclusions:
- Data support a lattice edge expansion model for immature capsid formation.
- This model follows a trimeric nucleation event.
- Provides insights into virus structural protein assembly dynamics in a biologically relevant context.
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