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Published on: August 13, 2016
Local cortical pulling-force repression switches centrosomal centration and posterior displacement in C. elegans
Akatsuki Kimura1, Shuichi Onami
1Computational and Experimental Systems Biology Group, RIKEN Genomic Sciences Center, Tsurumi, Yokohama 230-0045, Japan.
The Journal of Cell Biology
|December 26, 2007
Summary
Centrosome positioning relies on microtubule forces. Local repression of posterior cortical pulling forces switches migration from centering to displacement, a conserved mechanism for dynamic positioning.
Area of Science:
- Cell biology
- Developmental biology
- Biophysics
Background:
- Centrosome positioning is crucial for cell division and development.
- In Caenorhabditis elegans, centrosome migration involves centering and posterior displacement.
- Two key mechanisms are center-directed forces and polarized cortical pulling.
Purpose of the Study:
- To analyze the spatial distribution of forces regulating centrosome migration.
- To elucidate the mechanism switching centrosome migration from centering to displacement.
- To investigate the role of local force regulation in dynamic positioning.
Main Methods:
- Image processing to measure micrometer-scale centrosome movements.
- Analysis of spatial force distribution during migration.
- Computer simulations to model force regulation effects.
Main Results:
- Polarized cortical pulling forces are active during centering migration.
- Posteriorly directed cortical pulling is repressed laterally during centering.
- This repression is relieved during posterior displacement migration.
- Local repression of cortical pulling is sufficient to switch migration modes.
Conclusions:
- Local regulation of polarized cortical pulling drives the switch between centrosome centering and displacement.
- This mechanism ensures precise temporal control of centrosome positioning.
- The findings suggest a conserved regulatory strategy for dynamic cell organization.
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