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The site of RanGTP generation can act as an organizational cue for mitotic microtubules

Julia Zonis1, Andrew Wilde

  • 1Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.

Biology of the Cell
|June 23, 2011
PubMed
Abstract

Insights

RanGTP (Ran-GTPase-GTP) guides microtubule organization during cell division. Ectopic RanGTP generation at the cell membrane induced microtubule arrays, suggesting its location dictates microtubule growth and organization.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Cytoskeleton Dynamics

Background:

  • RanGTP is crucial for microtubule spindle assembly during mitosis.
  • Its localized generation on chromosomes suggests a role in spatial organization of spindle assembly.
  • Debate exists whether RanGTP acts as a spatial cue or general activator in somatic cells due to lack of sharp gradients.

Purpose of the Study:

  • To investigate if the site of RanGTP generation influences microtubule organization.
  • To determine if RanGTP can act as a spatial cue for microtubule organization in somatic cells.

Main Methods:

  • Ectopic generation of RanGTP at the plasma membrane in mitotic somatic cells.
  • Observation and analysis of resulting microtubule organization.

Main Results:

  • Ectopic RanGTP generation at the plasma membrane stimulated organized microtubule array formation.
  • This demonstrates that the location of RanGTP production can direct microtubule organization.

Conclusions:

  • The site of RanGTP generation provides spatial information for microtubule growth and organization.
  • This supports the role of RanGTP in specifying chromosome-centered spindle assembly during mitosis.

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