Epithelial Folding Driven by Apical or Basal-Lateral Modulation: Geometric Features, Mechanical Inference, and...

Area of Science:

• Developmental Biology
• Cell Biology
• Biophysics

Background:

• Epithelial folding is crucial for forming complex tissues and organs during embryonic development.
• Understanding the cellular forces that drive epithelial sheet morphology is less developed than molecular mechanisms.

Purpose of the Study:

• To develop a theoretical model for autonomous epithelial folding.
• To investigate how intracellular mechanical modulation influences fold formation and cell shape.
• To explore the robustness of folding against external mechanical perturbations.

Main Methods:

• A simple and general theoretical model for monolayered epithelial sheets.
• Analysis of active modulation of intracellular mechanics on apical and basal-lateral surfaces.
• Comparison of theoretical cell deformation with experimental measurements.

Main Results:

• Active intracellular mechanics can induce epithelial folding without buckling instability.
• Apical modulation leads to V-shaped folds, while basal-lateral modulation creates U-shaped folds.
• Cell shape changes depend on initial aspect ratios and modulation type, with theoretical predictions validated experimentally.

Conclusions:

• The theoretical model provides mechanical principles for autonomous epithelial folding.
• Folding mechanisms can be inferred from experimental data using this model.
• The findings offer guidance for studying epithelial folding in various biological systems.