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Updated: Jan 3, 2026
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Myosin-Specific Adaptations of In vitro Fluorescence Microscopy-Based Motility Assays
Published on: February 4, 2021
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Competition between two high- and low-affinity protein-binding sites in myosin VI controls its cellular function
Natalia Fili1, Yukti Hari-Gupta2, Bjork Aston2
1Sheffield Cancer Centre, Department of Oncology and Metabolism, University of Sheffield, Sheffield S10 2RX, United Kingdom.
The Journal of Biological Chemistry
|November 21, 2019
Summary
Myosin VI interacts with binding partners through distinct motifs, influencing its nuclear activity. Loss of DAB2, a tumor suppressor, may increase myosin VI transcription, potentially impacting cancer development.
Area of Science:
- Molecular Biology
- Cell Biology
Background:
- Myosin VI is a multifunctional protein involved in various cellular processes.
- Its diverse functions are regulated by alternative splicing and binding partner interactions.
- The interplay between these regulatory mechanisms is not well understood.
Purpose of the Study:
- To investigate the interaction dynamics between myosin VI and its binding partners.
- To explore how these interactions modulate myosin VI's nuclear functions, including DNA binding and transcriptional activity.
- To understand the implications of these interactions in the context of cancer.
Main Methods:
- Recombinant protein kinetic analysis.
- Fluorescence imaging of protein distribution in mammalian cells.
- In vitro assays to assess DNA binding and transcriptional activity.
Main Results:
- Myosin VI exhibits selectivity for binding partners via high- and low-affinity motifs, enabling partner competition.
- The low-affinity partner DAB2, at high concentrations, inhibits nuclear myosin VI's DNA binding and transcriptional activity.
- Loss of the tumor suppressor DAB2 may enhance myosin VI-mediated transcription.
Conclusions:
- Competition among myosin VI binding partners is a key regulatory mechanism.
- DAB2's interaction with myosin VI plays a critical role in regulating nuclear myosin VI activity.
- Altered myosin VI partner protein levels during cancer onset may lead to increased nuclear myosin VI activity, suggesting a role in tumorigenesis.
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