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Membrane Remodeling of Giant Vesicles in Response to Localized Calcium Ion Gradients
Published on: July 16, 2018
Dimpled vesicles: the interplay between energetics and transient pores.
Susan D Gillmor1, Paul S Weiss
1Department of Chemistry, George Washington University, 725 21st Street, N.W., Washington, DC 20052, USA.
The Journal of Physical Chemistry. B
|October 8, 2008
Summary
Red blood cells (RBCs) change shape in capillaries. This study mimics RBC discoid shape by creating area differences in lipid bilayers, revealing transient pores enable shape changes.
Area of Science:
- Biophysics
- Cell Biology
- Materials Science
Background:
- Red blood cells (RBCs) exhibit remarkable shape malleability, transitioning between discocytes, echinocytes, and stomatocytes in response to external stimuli.
- Previous research demonstrated that altering lipid leaflet composition influences RBC shape, with exterior additives promoting stomatocyte formation.
- RBC shape transformations are linked to the unique properties of the RBC bilayer and asymmetric leaflet surface areas.
Purpose of the Study:
- To investigate the energetic and geometric factors governing RBC shape transformations.
- To develop a model system that mimics the biconcave RBC discoid shape.
- To identify mechanisms enabling vesicles to achieve lower energy states through shape modulation.
Main Methods:
- Creation of a symmetrical lipid bilayer system designed to promote area differences between leaflets.
- Analysis of the energetic and geometric properties of the model system.
- Observation and characterization of vesicle shape changes.
Main Results:
- The developed system successfully mimicked the discoid shape of RBCs.
- Area-difference induction between lipid bilayer leaflets was achieved.
- Transient pore formation was identified as a key mechanism for vesicle deflation and profile reduction.
Conclusions:
- The study highlights the critical role of area-difference between lipid bilayer leaflets in controlling cell shape.
- Transient pores are crucial for enabling vesicles to adopt lower energy configurations.
- This research provides insights into the fundamental biophysics of cell shape regulation and membrane dynamics.
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