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The Mechanics of Poro-Elastic Contractile Actomyosin Networks As a Model System of the Cell Cytoskeleton
Published on: March 10, 2023
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Stress fibres are embedded in a contractile cortical network
Timothée Vignaud1,2,3, Calina Copos4, Christophe Leterrier5
1CytoMorpho Lab, Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire et Végétale, Grenoble-Alpes University/CEA/CNRS/INRA, Grenoble, France.
Nature Materials
|October 20, 2020
Summary
Actin filament bundles are embedded within a contractile cell network, enabling intracellular force distribution. This embedding is crucial for transmitting bundle contractions throughout the cell, impacting cell mechanics.
Area of Science:
- Cell biology
- Biophysics
- Cytoskeletal dynamics
Background:
- Contractile actomyosin networks generate intracellular forces.
- Actin filament bundles interconnect within the cell network.
- The mechanical role of these interconnections is not fully understood.
Purpose of the Study:
- To investigate the mechanical impact of actin filament bundle interconnections.
- To understand how these structures affect intracellular force production and distribution.
Main Methods:
- Hydrogel micropatterning to control cell shape and substrate properties.
- Traction force microscopy to measure cellular forces.
- Laser photoablation to probe network response to local perturbations.
Main Results:
- Actin bundles are fully embedded within a continuous, contractile cortical filament network.
- Bundle embedding is essential for propagating contractions across the cell.
- Bundles appear to form from aligned and coalesced cortical actin filaments.
Conclusions:
- The embedding of actin bundles in the cortical network is critical for force transmission.
- This structural organization dictates how intracellular forces are distributed.
- Understanding these mechanics provides insight into cell shape and movement.
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