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Updated: May 18, 2026
10:34
Ligand Nano-cluster Arrays in a Supported Lipid Bilayer
Published on: April 23, 2017
Random pinning limits the size of membrane adhesion domains
Thomas Speck1, Richard L C Vink
1Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany.
Summary
Membrane adhesion models predict domain formation, but random pinning disrupts this. This study demonstrates how cytoskeleton anchoring prevents macroscopic adhesion domains, a finding confirmed by simulations.
Area of Science:
- Biophysics
- Soft Matter Physics
- Computational Biology
Background:
- Theoretical models suggest membrane adhesion can lead to macroscopic phase separation into adhesion domains.
- Membrane height fluctuations are crucial for understanding adhesion properties.
Purpose of the Study:
- To investigate how random pinning, such as by cytoskeleton anchoring, alters membrane adhesion domain formation.
- To analyze the impact of restricted membrane height fluctuations on adhesion behavior.
Main Methods:
- Analytical calculations to predict the effects of quenched disorder.
- Large-scale Monte Carlo simulations utilizing an efficient composite Monte Carlo move.
- Simultaneous updates of membrane height and bond degrees of freedom.
Main Results:
- Random pinning induces quenched disorder of the random-field type.
- This disorder rigorously prevents the formation of macroscopic adhesion domains, consistent with the Imry-Ma argument.
- Analytical predictions were strikingly confirmed by Monte Carlo simulations.
Conclusions:
- Cytoskeleton-induced random pinning fundamentally alters membrane adhesion, preventing macroscopic domain formation.
- The concept of random-field disorder is critical for understanding adhesion in pinned membranes.
- The developed composite Monte Carlo move is efficient and applicable to other complex systems.
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