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Updated: Jun 5, 2026
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Reconstituting and Characterizing Actin-Microtubule Composites with Tunable Motor-Driven Dynamics and Mechanics
Published on: August 25, 2022
Active force generation in cross-linked filament bundles without motor proteins
1Department of Mechanical Engineering and Johns Hopkins Physical Science in Oncology Center, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
Cytoskeletal filaments generate contractile forces through cross-linker bonds, not just motors. This new theory explains bundle mechanics and active force generation in cells.
Area of Science:
- Cellular mechanics
- Biophysics
- Cytoskeletal dynamics
Background:
- Cytoskeletal filaments are crucial for cell structure and function.
- Lateral interactions via cross-linking proteins influence bundle mechanics.
- Active force generation in cytoskeletal bundles is not fully understood.
Purpose of the Study:
- To develop a theory linking molecular cross-linker properties to macroscale filament bundle mechanics.
- To investigate active force generation in filament bundles.
- To provide insights into cellular processes like cytokinesis and stress-fiber contraction.
Main Methods:
- Theoretical modeling of cross-linker bond formation and rupture.
- Calculation of the force-velocity relation for filament bundles.
- Analysis of molecular properties' impact on macroscopic behavior.
Main Results:
- Demonstrated significant contractile forces in filament bundles without molecular motors.
- Established a relationship between molecular cross-linker dynamics and bundle mechanics.
- The theory predicts active force generation driven by cross-linker turnover.
Conclusions:
- Cross-linker dynamics are a key mechanism for active force generation in cytoskeletal bundles.
- The theory offers a new perspective on passive and active mechanics of filament networks.
- Findings have implications for understanding cell division and cytoskeletal contractility.
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