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Myosin II contributes to cell-scale actin network treadmilling through network disassembly
Cyrus A Wilson1, Mark A Tsuchida, Greg M Allen
1Department of Biochemistry and Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California 94305, USA.
Nature
|May 21, 2010
Summary
Non-muscle myosin II drives actin network disassembly for cell crawling. This enzyme coordinates actin treadmilling, crucial for sustained cell motility and long-range coordination.
Area of Science:
- Cell Biology
- Biochemistry
- Biophysics
Background:
- Cell crawling relies on actin cytoskeleton dynamics, involving actin filament assembly at the leading edge and disassembly at the rear.
- ADF/cofilin proteins are known to aid actin disassembly, but their long-range coordination mechanisms remain unclear.
Purpose of the Study:
- To investigate the role of non-muscle myosin II in actin network disassembly during eukaryotic cell crawling.
- To elucidate how myosin II activity is coordinated for sustained cell motility.
Main Methods:
- Observing myosin II localization in motile fish keratocytes.
- Utilizing detergent-extracted cytoskeletons to study myosin II-mediated actin disassembly upon ATP activation.
- Assessing the impact of myosin II inhibition and actin filament stabilization on cell motility.
Main Results:
- Non-muscle myosin II is concentrated at the cell rear, correlating with high actin network disassembly rates.
- Myosin II activation in extracted cytoskeletons induced localized actin network disassembly.
- Simultaneous inhibition of myosin II and actin stabilization synergistically impaired cell motility, indicating distinct disassembly pathways.
Conclusions:
- Non-muscle myosin II acts as a key enzyme in actin network disassembly for cell motility.
- The formation and reorganization of actomyosin networks may provide an intrinsic timer for actin network treadmilling coordination in motile cells.
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