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Stress-shape misalignment in confluent cell layers
Mehrana R Nejad1, Liam J Ruske2, Molly McCord3,4
1The Rudolf Peierls Centre for Theoretical Physics, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, United Kingdom. mehrana@g.harvard.edu.
Nature Communications
|April 29, 2024
Summary
Cells can control their contractile forces independently of their shape during tissue formation. This discovery challenges previous assumptions about cell mechanics and offers new insights into tissue repair and development.
Area of Science:
- Cell biology
- Biophysics
- Developmental biology
Background:
- Epithelial cells generate active forces crucial for tissue formation and repair.
- It is commonly assumed that cellular contractile stresses align with cell body orientation.
Purpose of the Study:
- To investigate the relationship between cell shape and cell-generated contractile stresses.
- To determine if cellular contractile stresses can be decoupled from cell body orientation.
Main Methods:
- Simultaneous measurement of cell shape and cell-generated contractile stress orientations.
- Development of a continuum model to analyze stress and cell body dynamics.
Main Results:
- Observed dynamic domains where contractile stresses were systematically misaligned with cell body orientation.
- The developed continuum model successfully replicated the experimental spatial and temporal dynamics of stress misalignment.
- Demonstrated that cells control contractile forces independently of cell shape.
Conclusions:
- Cellular contractile forces are not rigidly coupled to cell shape.
- This decoupling suggests greater flexibility in the physical rules governing cell force generation and cell shape.
- Findings have implications for understanding tissue morphogenesis and repair mechanisms.
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