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Updated: Jul 31, 2026
10:52
Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets
Published on: August 13, 2016
Ran-GTP coordinates regulation of microtubule nucleation and dynamics during mitotic-spindle assembly
R E Carazo-Salas1, O J Gruss, I W Mattaj
1European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany. carazosa@embl-heidelberg.de
Nature Cell Biology
|March 7, 2001
Summary
Guanosine triphosphate-bound Ran (Ran-GTP) independently affects microtubule nucleation and stability, crucial for spindle assembly. Inhibiting Ran-GTP prevents bipolar spindle formation, even with intact chromosomes and centrosomes.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Ran-GTP is known to induce microtubule and pseudo-spindle assembly.
- Chromosomes generate Ran-GTP to assemble spindle microtubules in mitotic extracts.
Purpose of the Study:
- To investigate the independent effects of Ran-GTP on microtubule nucleation and dynamics.
- To determine the role of Ran-GTP in bipolar spindle assembly.
Main Methods:
- Utilized mitotic egg extracts.
- Examined microtubule nucleation and dynamics in response to Ran-GTP.
- Inhibited Ran-GTP production.
Main Results:
- Ran-GTP demonstrated independent effects on both centrosome nucleation activity and microtubule stability.
- Inhibition of Ran-GTP production blocked bipolar spindle assembly.
- This occurred despite the presence of duplicated centrosomes and kinetochores.
Conclusions:
- Ran-GTP plays a critical, independent role in regulating microtubule nucleation and stability.
- Ran-GTP is essential for the formation of a bipolar spindle during mitosis.
- Targeting Ran-GTP production is a potential strategy for disrupting spindle formation.
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