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Updated: May 31, 2026
06:37
Protrusion Force Microscopy: A Method to Quantify Forces Developed by Cell Protrusions
Published on: June 16, 2018
Podosome rings generate forces that drive saltatory osteoclast migration
Shiqiong Hu1, Emmanuelle Planus, Dan Georgess
1Laboratoire de Physique, UMR 5672, Lyon 69364, France.
Molecular Biology of the Cell
|July 9, 2011
Summary
Osteoclasts use dynamic actin structures called podosomes to generate forces that drive cell migration. These podosomes push outward, and their movement propels the osteoclast forward in a periodic jumping pattern.
Area of Science:
- Cell Biology
- Biophysics
- Mechanobiology
Background:
- Podosomes are actin-rich adhesion structures in cells.
- Podosomes self-organize into dynamic rings.
- Osteoclasts utilize podosomes for various functions.
Purpose of the Study:
- Investigate the role of podosome forces in osteoclast migration.
- Analyze the relationship between actin dynamics and cell movement.
- Elucidate the self-organization and force generation of podosome rings.
Main Methods:
- Observing osteoclasts on bead-seeded soft substrates.
- Analyzing substrate displacement around podosome rings.
- Tracking the centers of mass of the cell and actin (G and P).
Main Results:
- Podosome rings generate outward tension forces.
- Osteoclast migration occurs in a "jump" pattern.
- Cell and actin trajectories (G and P) are strongly correlated.
- Osteoclasts periodically catch up with podosome structures.
Conclusions:
- Podosome assemblies are involved in tension generation.
- Actin dynamics within osteoclasts drive cell migration.
- Podosomes actively propel osteoclasts during migration.
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