Phase transition induced fission in lipid vesicles
C Leirer1, B Wunderlich, V M Myles
1University of Augsburg, Experimental Physics I, D-86159 Augsburg, Germany.
Biophysical Chemistry
|May 16, 2009
Summary
Giant unilamellar vesicles (GUVs) utilize their gel-fluid phase transition to trigger membrane fission. This process, influenced by viscosity, results in vesicle rupture and the release of smaller vesicles.
Area of Science:
- Biophysics
- Materials Science
- Soft Matter Physics
Background:
- Giant unilamellar vesicles (GUVs) are model systems for studying cell membrane behavior.
- Phase transitions in lipid bilayers are crucial for membrane dynamics and function.
- Membrane fission is a fundamental process in cellular biology, involved in transport and division.
Purpose of the Study:
- To investigate the role of the first-order phase transition in GUVs as a trigger for membrane fission.
- To analyze the effect of temperature-induced phase transitions on GUV morphology and fission.
- To determine the influence of bulk viscosity on the GUV fission process and resulting vesicle size.
Main Methods:
- Inducing and observing phase transitions in GUVs through controlled temperature changes.
- Utilizing microscopy techniques to visualize GUV budding, pearling, and fission.
- Modifying the external medium's viscosity to mimic intracellular conditions and assessing its impact on fission.
Main Results:
- The gel-fluid phase transition in GUVs triggers membrane fission, leading to neck rupture and vesicle release.
- Heating GUVs through the transition causes pearling and subsequent breakup into multiple vesicles.
- Increased bulk viscosity significantly reduces the size of released vesicles without altering the fission mechanism.
Conclusions:
- The first-order phase transition of GUVs provides a tunable mechanism for membrane fission.
- Temperature-driven phase transitions offer a controllable method for inducing and studying membrane scission.
- Environmental factors like viscosity play a critical role in regulating the outcome of membrane fission events.
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