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Updated: Jul 29, 2026
06:26
Pulling Membrane Nanotubes from Giant Unilamellar Vesicles
Published on: December 7, 2017
Coiling instability of multilamellar membrane tubes with anchored polymers
I Tsafrir1, M A Guedeau-Boudeville, D Kandel
1Department of Physics of Complex Systems, The Weizmann Institute of Science, Rehovot 76 100, Israel.
Summary
Polymers with hydrophobic anchors induce coiling instability in phospholipid membranes, forming tight coils without twist or adhesion. This discovery offers new insights into membrane dynamics and polymer-membrane interactions.
Area of Science:
- Biophysics
- Materials Science
- Polymer Science
Background:
- Phospholipid membranes form cylindrical multilamellar stacks.
- Polymers with hydrophobic anchors can interact with lipid bilayers.
- Membrane coiling instabilities are typically associated with twist or adhesion.
Purpose of the Study:
- To experimentally investigate the coiling instability of phospholipid membranes induced by specific polymers.
- To develop and validate a model describing the relationship between membrane curvature and polymer concentration.
- To understand the conditions leading to maximally tight coil formation.
Main Methods:
- Experimental observation of coiling in phospholipid multilamellar stacks.
- Development of a theoretical model coupling local membrane curvature and polymer concentration.
- Imaging and comparison of experimental results with simulated coiled tube projections.
Main Results:
- Coiling instability was observed in the absence of twist and adhesion.
- A model successfully predicted maximally tight coils above a threshold polymer occupancy.
- Experimental data aligned with model predictions, including complex torsions and maximal curvature.
Conclusions:
- Local membrane curvature and polymer concentration are key coupled factors in inducing coiling.
- A critical polymer occupancy threshold exists for the formation of maximally tight coils.
- The findings provide a novel mechanism for membrane shape transformation driven by polymer interactions.
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