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Updated: May 18, 2026
08:55
Characterization of Multi-subunit Protein Complexes of Human MxA Using Non-denaturing Polyacrylamide Gel-electrophoresis
Published on: October 28, 2016
Antiparallel coiled-coil-mediated dimerization of myosin X
1Division of Life Science, State Key Laboratory of Molecular Neuroscience and Center of Systems Biology and Human Health, School of Science and Institute for Advanced Study, Hong Kong University of Science and Technology, Kowloon, Hong Kong, China.
Summary
Myosin X forms a unique antiparallel coiled-coil dimer (anti-CC), crucial for its function. Disrupting this dimer impairs myosin X
Area of Science:
- Molecular biology
- Cell biology
- Biochemistry
Background:
- Unconventional myosins drive cellular processes via actin filament movement.
- Motor dimerization is typically required for processive myosin movement.
- A common dimerization mechanism involves parallel coiled-coil formation.
Purpose of the Study:
- To investigate the dimerization mechanism of myosin X.
- To determine the role of the coiled-coil region in myosin X function.
- To elucidate how myosin X interacts with actin filaments.
Main Methods:
- Site-directed mutagenesis to disrupt the coiled-coil region.
- Biochemical assays to assess dimer stability.
- Filopodia induction assays to evaluate myosin X activity.
Main Results:
- Myosin X forms a stable antiparallel coiled-coil dimer (anti-CC).
- Disruption of the anti-CC abolished filopodial induction activity.
- A helical linker connects the anti-CC to the α-helical domain.
Conclusions:
- The antiparallel coiled-coil dimer is essential for myosin X function.
- Myosin X dimerization enables movement on single and bundled actin filaments.
- This unique dimerization mechanism expands our understanding of myosin motor function.
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