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Pulling Membrane Nanotubes from Giant Unilamellar Vesicles
Published on: December 7, 2017
Unexpected membrane dynamics unveiled by membrane nanotube extrusion
Clément Campillo1, Pierre Sens, Darius Köster
1Institut Curie, Centre de Recherche, Laboratoire Physico-Chimie, Paris, France. clement.campillo@univ-lyon1.fr
Biophysical Journal
|March 27, 2013
Summary
Cell membrane mechanics are complex. Unexpected friction in lipid membranes, not just cytoskeleton, explains cellular dynamics, highlighting the role of membrane proteins.
Area of Science:
- Cellular mechanics
- Biophysics
- Membrane biophysics
Background:
- Distinguishing plasma membrane and cytoskeleton roles in cell mechanics is challenging.
- Cytoskeleton presence is typically cited for differences between cellular and pure lipid membranes.
- Membrane nanotube extrusion is a common method to study these differences.
Purpose of the Study:
- To investigate the force responses of cell membranes independent of the cytoskeleton.
- To understand the dynamic behavior of synthetic liposomes compared to cellular membranes.
- To identify factors contributing to cell membrane rheology.
Main Methods:
- Studied force responses of plasma membrane spheres without cytoskeleton.
- Utilized synthetic liposomes with varied lipid content.
- Reconstituted actin cortices within liposomes.
Main Results:
- Tiny variations in synthetic membrane composition altered dynamic behavior, mimicking cellular membranes.
- This dynamic behavior was attributed to amplified intramembrane friction.
- Actin cortices inside liposomes added to, but did not dominate, membrane friction.
Conclusions:
- Intramembrane friction, influenced by membrane composition, significantly impacts cell membrane rheology.
- The role of membrane proteins in cell membrane rheology requires careful consideration.
- Cytoskeleton's contribution to membrane friction is not always dominant.
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