Domain formation in bicomponent vesicles induced by composition-curvature coupling

Area of Science:

• Biophysics
• Materials Science
• Computational Chemistry

Background:

• Lipid vesicles are crucial in biological systems, with their morphology influenced by lipid composition.
• Understanding phase separation and domain formation in biphasic lipid membranes is key to cell membrane function.

Purpose of the Study:

• To investigate the morphologies of biphasic lipid vesicles with differing spontaneous curvatures.
• To explore the formation of nano-domains and labyrinthine mesophases in lipid membranes.
• To elucidate the role of curvature mismatch, surface tension, and lipid-lipid interactions in membrane organization.

Main Methods:

• Intensive Monte Carlo numerical simulations were employed to model lipid vesicle behavior.
• Phase diagrams were constructed to map vesicle morphologies under varying conditions.
• Quantitative analysis of domain patterns using structure factor and domain size distribution.

Main Results:

• Simulations revealed various vesicle morphologies, including nano-domains and labyrinthine mesophases.
• Results quantitatively align with analytical predictions in the disordered phase.
• Exploration of the full parameter space, particularly near critical temperatures, provided new insights.

Conclusions:

• The study provides a mechanism explaining nano-domain formation in cell membranes.
• Computational modeling offers a powerful approach to study complex membrane phenomena.
• Findings contribute to understanding the physical basis of membrane organization and function.