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Spontaneous Formation and Rearrangement of Artificial Lipid Nanotube Networks as a Bottom-Up Model for Endoplasmic Reticulum
Published on: January 22, 2019
Domain-induced budding of fluid membranes.
1Institut für Festkörperforschung, Forschungszentrum Jülich, D-5170 Jülich, Germany.
Biophysical Journal
|May 12, 2009
Summary
Membrane domains grow until they become unstable, leading to budding or invagination. This process, driven by bending energy and line tension, can cause membrane rupture and domain pinching off.
Area of Science:
- Biophysics
- Cell Biology
- Membrane Dynamics
Background:
- Biological membranes are fluid structures composed of lipids and proteins.
- Membrane domains are localized regions within the membrane with distinct compositions.
- Domain growth occurs through lateral diffusion and molecular aggregation.
Purpose of the Study:
- To introduce a theoretical model for membrane domain instability and budding.
- To investigate the physical forces driving domain shape transitions.
- To explore the implications for membrane remodeling and vesicle formation.
Main Methods:
- Development of a simple theoretical model.
- Analysis of energy contributions (bending energy, line tension).
- Mathematical prediction of domain instability and shape changes.
Main Results:
- A critical domain size exists beyond which instability occurs.
- Instability leads to budding or invagination driven by competing energies.
- For lipid bilayers, this can result in membrane rupture and domain scission.
- The mechanism applies to both non-coated and clathrin-coated domains.
Conclusions:
- Membrane domain growth is limited by an instability mechanism.
- This mechanism provides a physical basis for membrane budding and scission.
- The findings are relevant to various biological processes involving membrane remodeling.
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