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Updated: May 12, 2025
09:45
Construction of Model Lipid Membranes Incorporating G-protein Coupled Receptors GPCRs
Published on: February 5, 2022
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Lipid-GPCR interactions in an asymmetric plasma membrane model
Jingjing Ji1, Edward Lyman1,2
1Department of Physics and Astronomy, University of Delaware, Newark, DE, USA. elyman@udel.edu.
Faraday Discussions
|May 8, 2025
Summary
Simulations reveal how the adenosine A2A receptor interacts with lipids and cholesterol in asymmetric and symmetric cell membranes. Phosphatidylserine interactions remain stable, while cholesterol binding is sensitive to membrane asymmetry.
Area of Science:
- Biochemistry
- Molecular Biology
- Computational Biophysics
Background:
- The adenosine A2A receptor (A2AR) is a G protein-coupled receptor involved in various physiological processes.
- Understanding A2AR's interaction with the cell membrane is crucial for drug development.
- Membrane lipid asymmetry plays a significant role in receptor function.
Purpose of the Study:
- To investigate the impact of lipid asymmetry on A2AR interactions in its active state.
- To compare A2AR's lipid and cholesterol binding in asymmetric versus symmetric membrane models.
Main Methods:
- Molecular dynamics simulations of A2AR in two distinct membrane environments: asymmetric and symmetric.
- Analysis of lipid-protein and cholesterol-protein interactions.
Main Results:
- Phosphatidylserine (PS) solvation around A2AR is insensitive to the loss of membrane asymmetry due to charged residues.
- Cholesterol interactions are sensitive to lipid asymmetry, with higher abundance in the exoplasmic leaflet.
- A specific cholesterol binding site on helix 6 is conserved across different membrane models.
Conclusions:
- Lipid asymmetry influences cholesterol binding to A2AR but not PS solvation.
- The identified cholesterol binding site on helix 6 is a stable interaction point.
- These findings provide insights into A2AR's membrane environment and potential drug targeting.
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