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Updated: May 19, 2025
10:46
Motility of Single Molecules and Clusters of Bi-Directional Kinesin-5 Cin8 Purified from S. cerevisiae Cells
Published on: February 2, 2022
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Motor clustering enhances kinesin-driven vesicle transport
Rui Jiang1, Qingzhou Feng2, Daguan Nong3
1Intercollege Program in Integrative and Biomedical Physiology, Pennsylvania State University, University Park, Pennsylvania; Department of Biomedical Engineering, Pennsylvania State University, University Park, Pennsylvania.
Biophysical Journal
|May 7, 2025
Summary
Long-distance intracellular transport relies on motor proteins. Motor protein clustering, not just number, significantly enhances vesicle travel distance, explaining discrepancies between lab and cell studies.
Area of Science:
- Cell Biology
- Biophysics
- Molecular Motors
Background:
- Intracellular vesicles utilize kinesin and dynein motors for transport.
- In vitro studies suggest kinesin-1's slow binding rate necessitates numerous motors for long-range transport, contrasting with in vivo observations.
Purpose of the Study:
- Reconstitute and analyze liposome motility driven by multiple kinesin-1 motors.
- Investigate the role of motor protein organization, specifically clustering, in enhancing transport efficiency.
Main Methods:
- Utilized GFP-labeled kinesin-1 motors to drive 120-nm liposome motility in vitro.
- Employed DNA scaffolds to control and cluster motor proteins on liposomes.
Main Results:
- Confirmed that high kinesin-1 motor numbers are required for long-distance transport, aligning with binding rate predictions.
- Demonstrated that clustering even a small number of motors (three) significantly increased liposome travel distances.
- Showed motor arrangement, independent of motor count, is critical for transport distance.
Conclusions:
- Motor protein clustering enhances vesicle transport efficiency.
- Differences in motor organization, not just number, may reconcile in vivo and in vitro findings on motor requirements for intracellular transport.
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