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Updated: Dec 14, 2025
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Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
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Revisiting Membrane Microdomains and Phase Separation: A Viral Perspective
Prabuddha Sengupta1, Jennifer Lippincott-Schwartz1
1Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA.
Viruses
|July 16, 2020
Summary
Retroviruses like HIV selectively incorporate host cell proteins and lipids into their viral membranes. This process, driven by lipid-based phase partitioning, is crucial for virus survival and infection.
Area of Science:
- Virology
- Cell Biology
- Biochemistry
Background:
- Retroviruses acquire specific host cell proteins and lipids during budding.
- This specialized viral envelope is essential for viral infectivity and survival.
Purpose of the Study:
- To review recent findings on the mechanism of protein and lipid sorting into retroviral membranes.
- To propose a model for HIV assembly site phase separation.
Main Methods:
- Live cell imaging of single virus assembly.
- Analysis of lipid and protein interactions during viral budding.
Main Results:
- Proteins and lipids sort into HIV membranes via lipid-based phase partitioning.
- Multimerizing HIV Gag induces a liquid-ordered lipid phase enriched in cholesterol and sphingolipids.
- Proteins with specific affinities partition into this lipid environment, enabling selective incorporation.
Conclusions:
- HIV Gag induces phase separation at the viral assembly site through lipid acyl chain coupling and membrane curvature changes.
- This phase-partitioning mechanism is likely conserved in other budding structures within cells.
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