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Updated: Jun 18, 2026
09:26
Pattern Generation for Micropattern Traction Microscopy
Published on: February 17, 2022
Distribution of traction forces associated with shape changes during amoeboid cell migration.
B Alonso-Latorre1, R Meili, E Bastounis
1Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA 92093-0411, USA.
Summary
Cell motility involves cyclic shape changes. Myosin II
Area of Science:
- Cell Biology
- Biophysics
Background:
- Amoeboid motility is a fundamental biological process driven by cyclic shape changes.
- Understanding the relationship between cell deformation and traction forces is crucial for cell migration studies.
Purpose of the Study:
- To analyze dominant modes of shape change during cell motility.
- To associate these shape changes with traction forces in Dictyostelium cells.
- To investigate the role of Myosin II activity in the motility cycle.
Main Methods:
- Utilized Principal Component Analysis (PCA) on time-lapse measurements of cell shape and traction forces.
- Compared wild-type (wt) Dictyostelium cells with Myosin II heavy chain null (mhcA-) and essential light chain null (mlcE-) mutants.
Main Results:
- Identified a few dominant modes (four accounting for 75% variance) of cell shape changes, including dilation/elongation, bending, and bulging.
- Observed similar shape change modes across wt, mlcE-, and mhcA- cells, but at a slower pace in Myosin II mutants.
- Found that sideways protrusion/retraction, linked to lateral traction force asymmetry, was less significant in mhcA- cells.
Conclusions:
- The mechanical cycle of cell shape and traction stresses is conserved across different Myosin II activities.
- Loss of myosin function slows down the motility cycle, likely due to altered spatial organization of traction stresses.
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