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Updated: May 29, 2026
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Transmembrane Domain Oligomerization Propensity determined by ToxR Assay
Published on: May 26, 2011
Transmembrane helices can induce domain formation in crowded model membranes
Jan Domański1, Siewert J Marrink, Lars V Schäfer
1Groningen Biomolecular Sciences and Biotechnology Institute, and Zernike Institute for Advanced Materials, University of Groningen, Nijemborgh 7, 9747 AG Groningen, The Netherlands.
Biochimica Et Biophysica Acta
|September 3, 2011
Summary
Simulations show that lipid tail length and cholesterol influence membrane domain formation. High protein concentrations can drive membrane phase separation and alter protein diffusion.
Area of Science:
- Biophysics
- Computational Biology
- Membrane Biophysics
Background:
- Cellular membranes exhibit complex lipid and protein compositions.
- Understanding lipid-protein interactions is crucial for membrane function.
Purpose of the Study:
- To investigate the role of lipid composition and transmembrane (TM) proteins in membrane phase separation using molecular dynamics simulations.
- To explore how TM proteins affect lipid domain formation and protein diffusion in model membranes.
Main Methods:
- Coarse-grained molecular dynamics simulations were employed.
- Model membranes composed of saturated lipids, unsaturated lipids, cholesterol, and TM protein models were studied.
Main Results:
- Reduced lipid tail length mismatch and cholesterol depletion decreased lipid domain segregation.
- High concentrations of TM helices induced phase separation into liquid-ordered (l(o)) and liquid-disordered (l(d)) domains.
- TM helices crowded the l(d) domain, significantly slowing protein diffusion and causing anomalous diffusion.
Conclusions:
- Coarse-grained simulations can effectively model lateral reorganization in complex model biomembranes.
- TM proteins play a significant role in driving membrane heterogeneity and influencing protein dynamics.
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