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Updated: Jun 25, 2026
06:26
Pulling Membrane Nanotubes from Giant Unilamellar Vesicles
Published on: December 7, 2017
Membrane tension lowering induced by protein activity.
M D El Alaoui Faris1, D Lacoste, J Pécréaux
1Institut Curie, Centre de Recherche; CNRS, UMR 168; Université Pierre et Marie Curie, Paris, F-75248 France.
Physical Review Letters
|March 5, 2009
Summary
Giant vesicles with bacteriorhodopsin pumps showed increased membrane fluctuations when pumps were activated. This suggests the pumps lower the membrane
Area of Science:
- Biophysics
- Membrane Biophysics
- Soft Matter Physics
Background:
- Giant vesicles are model systems for cell membranes.
- Bacteriorhodopsin pumps are light-activated proteins embedded in membranes.
- Membrane fluctuations are sensitive to mechanical properties like tension.
Purpose of the Study:
- To investigate the effect of activated bacteriorhodopsin pumps on giant vesicle membrane dynamics.
- To measure the fluctuation spectrum of giant vesicles.
- To understand how protein activity influences membrane mechanics.
Main Methods:
- Videomicroscopy was used to observe and measure vesicle fluctuations.
- Analysis of the fluctuation spectrum in different wave vector regions.
- Giant vesicles containing bacteriorhodopsin pumps were prepared.
Main Results:
- A significant increase in membrane fluctuations was observed in the low wave vector region upon pump activation.
- The observed increase in fluctuations is interpreted as a reduction in effective membrane tension.
- Videomicroscopy provided quantitative measurements of these dynamic changes.
Conclusions:
- Light-activated bacteriorhodopsin pumps can actively modify the mechanical properties of giant vesicle membranes.
- The findings suggest a mechanism for light-induced changes in membrane tension.
- This study provides insights into the interplay between protein function and membrane biophysics.
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