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Published on: February 14, 2016
Conversion of Unc104/KIF1A kinesin into a processive motor after dimerization
Michio Tomishige1, Dieter R Klopfenstein, Ronald D Vale
1The Howard Hughes Medical Institute and the Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94143, USA.
Science (New York, N.Y.)
|September 28, 2002
Summary
Unc104/KIF1A, a kinesin motor, moves unidirectionally and processively, challenging previous notions of its biased diffusional motion. This suggests motor dimerization regulates its transport mechanism in living cells.
Area of Science:
- Molecular motor function
- Cellular transport mechanisms
- Kinesin superfamily proteins
Background:
- Unc104/KIF1A is a monomeric kinesin motor.
- Previous studies suggested it exhibits biased diffusional motion, unlike conventional kinesins.
- Its unusual motility mechanism was poorly understood.
Purpose of the Study:
- To investigate the motility mechanism of Unc104/KIF1A.
- To determine if Unc104/KIF1A exhibits unidirectional and processive movement.
- To explore the role of dimerization in Unc104/KIF1A function.
Main Methods:
- In vitro motility assays.
- Analysis of Unc104/KIF1A dimerization.
- High-speed single-molecule imaging.
Main Results:
- Unc104/KIF1A was shown to dimerize.
- Dimerized Unc104/KIF1A moves unidirectionally and processively along microtubules.
- Observed velocities are characteristic of intracellular transport.
Conclusions:
- Unc104/KIF1A operates via a mechanism similar to conventional kinesins in vivo.
- Motor dimerization is a key factor in regulating Unc104/KIF1A transport.
- This finding provides new insights into the regulation of kinesin motors.
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