Patterning and dynamics of membrane adhesion under hydraulic stress

Area of Science:

• Biophysics
• Cell Biology
• Developmental Biology

Background:

• Hydraulic fracturing is crucial for cavity formation in embryonic development, creating lumens from microlumens at cell-cell contacts.
• The underlying physical mechanisms of this process are complex and not fully understood within biological systems.

Purpose of the Study:

• To investigate the physical mechanisms of hydraulic fracturing and microlumen formation using a simplified model system.
• To establish a physical framework for understanding cell-cell adhesion reconfiguration driven by fluid pressure.

Main Methods:

• Experiments using adhered lipid vesicles subjected to osmotic stress to mimic cellular microlumen formation.
• Theoretical modeling and numerical simulations to analyze the physical processes.
• Systematic mapping of microlumen formation conditions, dynamics, and maturation.

Main Results:

• Adhered lipid vesicles form hydraulic microlumens under osmotic stress, similar to biological cells.
• Identified conditions for microlumen formation, observed dynamical patterns, and maturation processes.
• Demonstrated control over hydraulic fracturing by manipulating pressure gradients and membrane bond properties.

Conclusions:

• A physical framework for hydraulic reconfiguration of cell-cell adhesions has been established using lipid vesicles.
• Unexpected passive transition of microlumens to closed buds suggests a physical mechanism for adhesion remodeling via endocytosis.