Related Experiment Videos
Coiling instabilities of multilamellar tubes.
1Department of Physics, University of California, Santa Barbara, CA 93106, USA. santa@mrl.ucsb.edu
Summary
Myelin figures, or membrane stacks, can spontaneously coil or form double helices due to instabilities. These membrane structures lack inherent chirality but develop it under specific conditions, impacting their shape.
Area of Science:
- Membrane biophysics
- Soft matter physics
- Materials science
Background:
- Myelin figures are stacks of lipid bilayers forming coaxial cylinders.
- These structures are generally considered achiral.
- Understanding their stability is crucial for lipid self-assembly studies.
Purpose of the Study:
- To investigate the instabilities in myelin figures.
- To determine conditions under which myelin figures lose chiral symmetry.
- To explore the behavior of unilamellar vesicles.
Main Methods:
- Theoretical analysis of lipid bilayer mechanics.
- Mathematical modeling of cylindrical membrane stacks.
- Simulation of vesicle instabilities.
Main Results:
- Cylindrical membrane stacks develop instability with spontaneous curvature or decreased inter-membrane distance.
- This instability breaks chiral symmetry, leading to coiling or double helix formation.
- Unilamellar vesicles exhibit axisymmetric instability, potentially related to pearling.
Conclusions:
- Myelin figure coiling is an emergent property driven by specific physical conditions, not intrinsic chirality.
- Membrane curvature and spacing are key factors in myelin figure morphology.
- Vesicle instabilities offer insights into membrane dynamics and shape transitions.