A multicellular star-shaped actin network underpins epithelial organization and connectivity

Area of Science:

• Cell Biology
• Biophysics
• Tissue Engineering

Background:

• Epithelial tissues rely on bicellular junctions and actomyosin networks for integrity.
• The synergistic role of these structures in maintaining tissue organization is not fully understood.

Purpose of the Study:

• To identify and characterize a tissue-scale actomyosin network in the adult murine intestinal villi and an ex vivo organoid model.
• To elucidate the functional role of this network in maintaining epithelial integrity and organization.

Main Methods:

• Identification of a supracellular actomyosin network composed of actin stars and bicellular junctions.
• Laser ablation experiments to analyze the biomechanical properties and effects on epithelial arrangement.
• Analysis of cell shape, packing, and protrusive activity.

Main Results:

• A novel star-shaped supracellular actomyosin network was identified in intestinal villi and organoid epithelia.
• Actin stars maintain epithelial morphological stability by preserving cell shape and packing.
• This network limits cell migration and tissue disruption by acting as basal locks.

Conclusions:

• The star-shaped supracellular actin network is a key biomechanical system for epithelial layer coordination.
• This network plays a critical role in maintaining tissue organization and stability.
• Findings provide insights into epithelial mechanics relevant to development and disease.