Polymer motors: pushing out the front and pulling up the back
1Department of Mathematics, University of California, Davis, CA 95616, USA. mogilner@math.ucdavis.edu
Current Biology : CB
|September 19, 2003
Summary
Cellular mechanical work relies on motor proteins and polymer dynamics. This review explores how actin and microtubule polymers generate forces for essential cellular processes like movement and division.
Area of Science:
- Cellular mechanics and biophysics
- Cytoskeletal dynamics and polymer physics
Background:
- Cells utilize specialized motor proteins and polymer assembly/disassembly for mechanical work.
- Understanding the mechanisms of force generation by cytoskeletal polymers is crucial for cell biology.
Purpose of the Study:
- To review the mechanisms of force generation by actin and microtubule filaments.
- To discuss the organizational principles of actin networks and their role in cellular processes.
- To highlight examples of cellular forces generated by polymer gel dynamics.
Main Methods:
- Review of existing literature on cytoskeletal motor proteins.
- Analysis of polymer assembly and disassembly mechanisms.
- Examination of actin network organization and function.
Main Results:
- Actin and microtubule filaments act as 'one-shot' motors, generating pushing and pulling forces.
- Polymer dynamics are fundamental to intracellular pathogen propulsion, lamellipodia protrusion, and mitotic movements.
- Assembly and disassembly of polymer gels contribute significantly to cellular force generation.
Conclusions:
- Cytoskeletal polymers are key regulators of cellular mechanical work.
- Understanding polymer-based force generation provides insights into fundamental cell behaviors.
- The principles discussed apply to diverse cellular functions, from motility to division.
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