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Updated: Sep 11, 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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Evidence for Motility Determinants in the Kinesin-1 Minimal Motor Core Domain From Tether Variations.
Rieko Sumiyoshi1, Masahiko Yamagishi1,2, Junichiro Yajima1,2,3
1Department of Life Sciences Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
Cytoskeleton (Hoboken, N.J.)
|August 18, 2025
Summary
Artificial tethers engineered into kinesin-1 motor domains alter movement direction. Tether properties like stiffness and attachment site influence motor protein motility and directionality.
Area of Science:
- Molecular Motor Proteins
- Cellular Mechanics
- Biophysics
Background:
- Kinesin-1 is a dimeric motor protein that moves towards microtubule plus-ends.
- The mechanism of force generation and directional movement by minimal kinesin-1 motor domains is not fully understood.
Purpose of the Study:
- To investigate how engineered artificial tethers affect the motility of kinesin-1 monomers.
- To determine if tether properties (charge, length, stiffness) influence motor domain directionality and microtubule-gliding velocity.
Main Methods:
- Engineering artificial tethers (PEG, ssDNA, dsDNA) within the kinesin-1 motor domain.
- Utilizing in vitro gliding assays to measure microtubule-gliding velocity.
- Analyzing the effect of tether properties and attachment position on motor protein motility.
Main Results:
- Long, stiff tethers attached to the neck-linker decreased microtubule-gliding velocity.
- Tethers engineered at loop-12 induced consistent minus-end-directed motility, reversing normal kinesin-1 polarity.
- Tethers at loop-3 altered directionality based on tether stiffness.
Conclusions:
- The minimal motor domain contains determinants for motility.
- Artificial tethers can influence the directionality and velocity of kinesin-1 minimal motor domains.
- Tether properties and attachment site collectively modulate motor protein movement.
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