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Updated: Jun 3, 2026
07:31
Realistic Membrane Modeling Using Complex Lipid Mixtures in Simulation Studies
Published on: September 1, 2023
Membrane texture induced by specific protein binding and receptor clustering: active roles for lipids in cellular
E B Watkins1, C E Miller, J Majewski
1Biophysics Graduate Group, University of California, Davis, CA 95616, USA.
Summary
Cholera toxin binding alters lipid packing in biological membranes, creating new lipid phases and ordered structures. This lipid ordering may mediate cell signaling and influence toxin uptake.
Area of Science:
- Biophysics
- Cell Biology
- Structural Biology
Background:
- Biological membranes are dynamic structures essential for cellular functions.
- Lipid and protein interactions significantly influence membrane properties and cellular responses.
- Understanding molecular-level membrane changes is crucial for deciphering cellular mechanisms.
Purpose of the Study:
- To investigate molecular-level changes in lipid organization upon multivalent toxin binding.
- To analyze structural alterations in lipid monolayers and bilayers induced by cholera toxin.
- To explore the role of lipid ordering in cell signaling and toxin endocytosis.
Main Methods:
- Grazing incidence X-ray diffraction was employed to study lipid monolayers and bilayers.
- Structural changes were analyzed before and after cholera toxin binding to membrane receptors.
- Experiments were conducted at biologically relevant surface pressures.
Main Results:
- Cholera toxin binding perturbed lipid packing in both monolayers and bilayers.
- New lipid phases with orientational texture emerged due to protein binding.
- Altered lipid order in the outer membrane leaflet was transmitted to the inner leaflet.
Conclusions:
- Multivalent protein binding can induce significant lipid structural changes and ordering.
- Lipid-mediated outside-in signaling is a potential mechanism following protein binding.
- Ordered lipid micro-domains may act as nucleation sites for clathrin-independent endocytosis.
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