Related Experiment Video
Updated: Jun 20, 2026
12:35
Optogenetic Inhibition of Rho1-Mediated Actomyosin Contractility Coupled with Measurement of Epithelial Tension in Drosophila Embryos
Published on: April 14, 2023
Adhesion-driven rigidity transition decoupled from density-driven jamming triggers epithelial organization in
Laura Rustarazo-Calvo1,2, Cristina Pallares-Cartes1, Adrián Aguirre-Tamaral3
1European Molecular Biology Laboratory Heidelberg, Developmental Biology Unit, Heidelberg, Germany.
Nature Physics
|June 19, 2026
Summary
Tissue material properties are regulated by phase transitions, crucial for morphogenesis. Adhesion strength, not cell density, primarily determines tissue rheology, enabling developmental switches.
Area of Science:
- Developmental Biology
- Biophysics
- Tissue Engineering
Background:
- Tissue material properties are actively regulated via phase transitions, essential for morphogenesis.
- These transitions occur at critical points in parameters like cell density, shape, and adhesion, but their interdependence is unclear.
Purpose of the Study:
- To investigate the interdependence of control parameters in regulating tissue material properties and morphogenetic trajectories.
- To identify the primary determinant of tissue rheology and explore its role in switching morphogenetic programs.
Main Methods:
- Theoretical phase diagram definition for zebrafish pluripotent tissues during epiboly.
- In vivo modulation of cell density, connectivity, and adhesion using optogenetics, biophysical measurements, and quantitative morphometrics.
Main Results:
- Zebrafish pluripotent tissues simultaneously cross critical points in cell density, connectivity, and adhesion during epiboly.
- Adhesion strength was identified as the main determinant of tissue rheology.
- Adhesion-driven rigidification in unjammed pluripotent tissues switched their morphogenetic program, triggering epithelial organization via tricellular junction formation, lumenogenesis, and apical polarity initiation.
Conclusions:
- Co-regulation of multiple parameters allows tissues to tune deformability and morphogenetic trajectory.
- Adhesion is a key regulator of emergent tissue mechanics, driving tissue organization and morphogenesis.
- Nonlinear dynamics of tissue mechanics are fundamental mechanisms for tissue organization and developmental processes.
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