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Updated: Mar 25, 2026
10:36
Measurements of Physiological Stress Responses in C. Elegans
Published on: May 21, 2020
15.2K
Fiber networks amplify active stress.
Pierre Ronceray1, Chase P Broedersz2, Martin Lenz3
1Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS), CNRS, Université Paris-Sud, Université Paris-Saclay, 91405 Orsay, France;
Summary
Molecular motor proteins generate forces essential for biological functions. This study reveals how disordered fiber networks amplify these forces through collective fiber buckling, leading to isotropic contraction in cells and tissues.
Area of Science:
- Biophysics
- Cell Biology
- Soft Matter Physics
Background:
- Large-scale force generation by motor proteins is crucial for cellular processes like motility and development.
- Disordered fiber networks transmit molecular forces, creating active stresses, but the underlying mechanisms are poorly understood.
Purpose of the Study:
- To theoretically investigate force transmission mechanisms within disordered fiber networks.
- To understand how microscopic active units generate large-scale stresses in biological tissues.
Main Methods:
- Theoretical modeling of force transmission in disordered fiber networks.
- Analysis of collective fiber buckling near local active units.
Main Results:
- Collective fiber buckling rectifies stress, leading to amplified isotropic contraction.
- Network disorder enhances stress amplification, which saturates at high active unit densities.
- Predictions align with experimental data from reconstituted tissues and actomyosin networks.
Conclusions:
- The microstructure of disordered fiber networks significantly shapes active stresses.
- Fiber buckling is a key mechanism for stress amplification in biological systems.
- Findings provide insights into force generation in cellular and tissue mechanics.
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