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Updated: Mar 15, 2026
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Probing Myosin Ensemble Mechanics in Actin Filament Bundles Using Optical Tweezers
Published on: May 4, 2022
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ATP-dependent interplay between local and global conformational changes in the myosin motor
Farooq Ahmad Kiani1,2, Stefan Fischer1
1Interdisciplinary Center for Scientific Computing (IWR), Im Neuenheimer Feld 205, University of Heidelberg, Heidelberg, D-69120, Germany.
Cytoskeleton (Hoboken, N.J.)
|September 2, 2016
Summary
Myosin
Area of Science:
- Biochemistry
- Molecular Biology
- Structural Biology
Background:
- The myosin motor head's ATPase active site drives muscle contraction.
- The Lymn-Taylor cycle involves conformational changes linked to ATP binding, hydrolysis, and product release.
- Understanding these dynamics is crucial for muscle function.
Purpose of the Study:
- To present a comprehensive atomic-level model of myosin's computational studies.
- To elucidate the coupling mechanisms between the active site and motor domain movements.
- To detail the precise timing of ATPase activation during the actomyosin cycle.
Main Methods:
- Atomic-level computational modeling of myosin.
- Generation of molecular movies to visualize domain motions.
- Analysis of conformational changes during ATP-induced actin dissociation and recovery stroke.
Main Results:
- Small active site changes trigger large motor domain transitions (e.g., actin cleft opening/closing, lever arm movement).
- Molecular movies reveal coupled domain motions and catalytic group positioning.
- ATP hydrolysis is precisely timed to occur after actin unbinding and lever arm priming.
Conclusions:
- The ATP-site acts as a central allosteric control unit in myosin motors.
- Coupling mechanisms ensure efficient motor function by precise timing of ATPase activity.
- These principles are fundamental to the operation of all myosin motors.
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