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Updated: Jun 28, 2026
10:52
Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets
Published on: August 13, 2016
Ncd motor binding and transport in the spindle
Mark A Hallen1, Zhang-Yi Liang, Sharyn A Endow
1Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.
Journal of Cell Science
|October 30, 2008
Summary
The kinesin-14 motor Ncd
Area of Science:
- Cell Biology
- Molecular Motors
- Cytoskeleton Dynamics
Background:
- The kinesin-14 motor Ncd is crucial for meiotic spindle assembly in Drosophila oocytes.
- Ncd generates opposing forces in mitotic spindles, but its binding mechanisms remain unclear.
Purpose of the Study:
- To investigate the binding mechanisms of the Ncd motor to the spindle.
- To determine the roles of the Ncd head and tail domains in spindle binding and function.
Main Methods:
- Analysis of Ncd mutants lacking the head or tail domains.
- Fluorescence photobleaching assays to study binding kinetics.
- Fluorescence flow analysis to track Ncd transport dynamics.
Main Results:
- The Ncd tail is essential for spindle and centrosome binding.
- Both head and tail domains are required for proper spindle assembly and function.
- A new model describes Ncd transport towards the equator, with the tail mediating tight binding and the head showing weak binding.
Conclusions:
- Ncd's tail domain plays a dominant role in its tight binding to the spindle.
- Ncd is transported towards microtubule plus-ends, opposing its motor direction, to generate force during mitosis.
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02:27The Mitotic Spindle
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02:27The Mitotic Spindle
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02:11Forces Acting on Chromosomes
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