Spontaneous Curvature Sculpts Filament-Vesicle Morphogenesis

Area of Science:

• Cell Biology
• Biophysics
• Materials Science

Background:

• Membrane-bound filaments are crucial for cellular morphogenesis.
• Understanding filament-membrane coupling under geometric confinement is limited.
• The role of spontaneous curvature in this process is not well understood.

Purpose of the Study:

• To investigate how spontaneous curvature regulates filament-membrane coupling.
• To explore the effects of spontaneous curvature on filament-membrane morphogenesis in vesicles.
• To develop a framework for predicting morphological transitions.

Main Methods:

• Developed a unified curvature-elasticity framework.
• Coupled membrane and filament curvature energetics.
• Constructed phase diagrams for vesicles with enclosed filament loops.

Main Results:

• Spontaneous curvature reorganizes filament-membrane morphogenesis by biasing membrane deformation versus filament bending.
• Distinct symmetry-breaking pathways were identified, leading to continuous and discontinuous morphological transitions.
• An intrinsic accommodation limit was found in the rigid-filament limit due to membrane elasticity and conservation laws.

Conclusions:

• Spontaneous curvature is a key factor in filament-membrane morphogenesis.
• It acts as a design parameter for controlling cellular shape.
• Findings are applicable to both biological and synthetic systems.