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Updated: Aug 5, 2025
08:57
Myosin-Specific Adaptations of In vitro Fluorescence Microscopy-Based Motility Assays
Published on: February 4, 2021
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Endocytic myosin-1 is a force-insensitive, power-generating motor
Ross Ta Pedersen1,2,3, Aaron Snoberger4,3, Serapion Pyrpassopoulos4
1Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720.
Biorxiv : the Preprint Server for Biology
|March 30, 2023
Summary
Yeast type I myosin, Myo5, generates power during endocytosis rather than acting as a force-sensitive anchor. Phosphorylation significantly activates this motor, influencing its role in cellular processes.
Area of Science:
- Cell Biology
- Molecular Motors
- Biophysics
Background:
- Myosins are crucial for clathrin-mediated endocytosis, but their exact functions remain unclear due to limited biophysical data.
- Understanding myosin mechanochemistry is key to elucidating their roles in endocytosis.
Approach:
- Investigated the in vitro force-dependent kinetics of Saccharomyces cerevisiae endocytic type I myosin, Myo5.
- Analyzed Myo5's working stroke and actin-detachment kinetics under varying forces.
Key Points:
- Myo5 exhibits low-duty-ratio motor activity.
- Phosphorylation activates Myo5 approximately 10-fold.
- Myo5's kinetics are largely force-insensitive, resembling cardiac myosin more than anchoring myosins.
Conclusions:
- Myo5 likely generates power to enhance actin assembly forces during endocytosis.
- This study provides novel insights into the mechanochemical properties of Myo5.
- The findings suggest a power-generating role for Myo5 in cellular endocytic events.
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