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Updated: May 14, 2026
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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
Interplay between myosin IIA-mediated contractility and actin network integrity orchestrates podosome composition and
K van den Dries1, M B M Meddens, S de Keijzer
1Department of Tumor Immunology, Radboud University Nijmegen Medical Centre, 6500 HB Nijmegen, The Netherlands.
Nature Communications
|January 31, 2013
Summary
Dendritic cells use actomyosin-based podosomes to sense their environment. Actin polymerization drives protrusion, while myosin IIA balances this to regulate podosome size and cell migration.
Area of Science:
- Cell biology
- Immunology
- Biophysics
Background:
- Tissue-resident dendritic cells are crucial for immune surveillance and migration.
- Podosomes are dynamic actomyosin-based structures that dendritic cells use to interact with the extracellular matrix.
- Understanding podosome mechanics is key to deciphering dendritic cell function.
Purpose of the Study:
- To elucidate the coordinated regulation of podosome protrusive cores and adhesive rings by the actomyosin apparatus.
- To reveal the interplay between actin polymerization and myosin IIA in controlling podosome dynamics.
- To provide mechanistic insights into how dendritic cells sense and remodel their environment via podosomes.
Main Methods:
- Live-cell imaging of podosome dynamics in dendritic cells.
- Perturbation of actin polymerization and myosin IIA activity.
- Analysis of cytoskeletal protein recruitment (vinculin, zyxin) to podosome rings.
Main Results:
- Actin polymerization drives podosome protrusion by expanding the protrusive core.
- Tension generated by actin polymerization recruits vinculin and zyxin, maintaining ring integrity.
- Myosin IIA-mediated contraction counterbalances core growth, regulating podosome size and protrusion.
- A novel interplay between actin and myosin IIA in podosome regulation was identified.
Conclusions:
- The actomyosin apparatus dynamically coordinates podosome core and ring behavior.
- Dendritic cell podosomes integrate cytoskeletal forces for environmental sensing and remodeling.
- These findings offer new mechanistic understanding of cell migration and immune surveillance.
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