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Updated: Jun 19, 2026
10:08
Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
Cholesterol-dependent phase separation in cell-derived giant plasma-membrane vesicles.
Ilya Levental1, Fitzroy J Byfield, Pramit Chowdhury
1Department of Bioengineering, University of Pennsylvania, 1010 Vagelos Laboratories, 3340 Smith Walk, Philadelphia, PA 19104, USA.
The Biochemical Journal
|October 9, 2009
Summary
Cholesterol levels dictate lipid phase separation and domain stability in cell membranes. This study used giant plasma-membrane vesicles to show cholesterol
Area of Science:
- Biochemistry
- Cell Biology
- Membrane Biophysics
Background:
- Lipid phase separation is crucial for plasma membrane function.
- Cholesterol is a key regulator of membrane properties.
- Giant plasma-membrane vesicles (GPMVs) offer a biologically relevant model system.
Purpose of the Study:
- To investigate the cholesterol-dependence of lipid domain formation and stability in cell membranes.
- To correlate cholesterol levels with the liquid-ordered phase fraction.
- To understand the effect of cholesterol on miscibility transition temperature.
Main Methods:
- Utilized cell-derived giant plasma-membrane vesicles (GPMVs).
- Analyzed lipid phase separation and domain stability.
- Employed fluorescence correlation spectroscopy to study diffusion.
Main Results:
- Cholesterol levels directly correlate with the abundance of the liquid-ordered phase.
- Miscibility transition temperature is cholesterol-dependent and linked to detergent-insoluble membranes.
- Two distinct diffusing populations were identified in phase-separated GPMVs.
Conclusions:
- Cholesterol significantly impacts lipid phase separation and domain stability in the plasma membrane.
- Findings in GPMVs align with observations in both model systems and live cells.
- This study provides insights into cholesterol's role in complex membrane environments.
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