Coarse-graining the vertex model and its response to shear.
Gloria Triguero-Platero1, Falko Ziebert1, Luis L Bonilla2
1Institute for Theoretical Physics, Heidelberg University, D-69120 Heidelberg, Germany.
Physical Review. E
|November 18, 2023
Summary
Researchers developed a new continuum model for cell monolayers by coarse-graining the active vertex model. This model describes tissue dynamics and collective cell motion, offering insights into cell shape and flow interactions.
Area of Science:
- Biophysics
- Computational Biology
- Cellular Mechanics
Background:
- Tissue dynamics and collective cell motion are fundamental biological processes.
- Existing simulation models like the active vertex model partially explain experimental observations.
- A robust continuum description for cellular tissues is still needed.
Purpose of the Study:
- To derive a macroscopic continuum description for a two-dimensional cell monolayer.
- To coarse-grain the active vertex model using the Poisson bracket approach.
- To analyze the stability of steady states and behavior under shear.
Main Methods:
- Coarse-graining the active vertex model via the Poisson bracket approach.
- Derivation of macroscopic equations for cell density, velocity, and the cellular shape tensor.
- Analysis of homogeneous steady states, their stability, and response to external shear.
Main Results:
- Successfully derived continuum equations for cell monolayer dynamics.
- Identified that stability of steady states aligns with thermodynamic stability.
- Elucidated the interplay between tissue flow and cellular shape under shear.
Conclusions:
- The derived macroscopic equations provide a foundational framework for tissue modeling.
- This work advances the understanding of collective cell behavior and tissue mechanics.
- The model serves as a basis for incorporating cell motion and morphogenetic processes.
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