Abstract
Heterotrimeric kinesin-2 motors [1,2] transport intraflagellar transport (IFT)-particles from the base to the tip of the axoneme to assemble and maintain cilia [3-10]. These motors are distinct in containing two non-identical motor subunits together with an accessory subunit [1,11-15]. We evaluated the significance of this organization by comparing purified wild type kinesin-2 holoenzymes that support IFT in vivo, with mutant trimers containing only one type of motor domain that do not support IFT in vivo. In motility assays, wild type kinesin-2 moved microtubules (MTs) at a rate intermediate between the rates supported by the two mutants. Interestingly, one of the mutants, but not the other mutant or the wild type protein, was observed to drive a persistent counter-clock-wise rotation of the gliding MTs. Thus one of the two motor domains of heterotrimeric kinesin-2 exerts torque as well as axial force as it moves along a MT, which may allow kinesin-2 to control its circumferential position around a MT doublet within the cilium.
Original language | English (US) |
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Pages (from-to) | 53-57 |
Number of pages | 5 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 401 |
Issue number | 1 |
DOIs | |
State | Published - Oct 8 2010 |
Keywords
- Heterotrimeric kinesin-2
- Intraflagellar transport
- Torque generation
ASJC Scopus subject areas
- Biochemistry
- Biophysics
- Cell Biology
- Molecular Biology