Stabilization of membrane necks by adhesive particles, substrate surfaces, and constriction forces

Area of Science:

• Biophysics
• Cell Biology
• Membrane Dynamics

Background:

• Membrane neck formation and closure are crucial for vesicle budding and cell division.
• Existing models often overlook the influence of adhesive surfaces on neck stability.
• Biological processes like endocytosis and cytokinesis involve neck formation near surfaces.

Purpose of the Study:

• To establish generalized stability conditions for membrane necks forming near adhesive surfaces.
• To investigate the interplay between membrane curvature elasticity, adhesion, and constriction forces.
• To introduce a novel intrinsic engulfment force.

Main Methods:

• Theoretical analysis of curvature elasticity, membrane-substrate adhesion, and constriction forces.
• Numerical energy minimization to validate stability conditions.
• Exploration of stability in various experimentally relevant systems.

Main Results:

• Derived generalized stability conditions for closed membrane necks.
• Validated theoretical conditions through numerical simulations.
• Demonstrated applicability to systems like supported lipid bilayers and bacterial outer membrane vesicles.

Conclusions:

• Membrane-substrate adhesion significantly influences neck stability during membrane remodeling.
• The intrinsic engulfment force provides a new framework for understanding adhesion-driven membrane processes.
• Findings offer insights into diverse cellular events involving membrane neck closure.