CHD4 is a RanGTP-dependent MAP that stabilizes microtubules and regulates bipolar spindle formation
Hideki Yokoyama1, Konstantinos Nakos2, Rachel Santarella-Mellwig1
1European Molecular Biology Laboratory, Meyerhofstrasse 1, Heidelberg 69117, Germany.
Current Biology : CB
|November 26, 2013
Summary
Chromatin remodeler CHD4 acts as a microtubule-associated protein (MAP) that stabilizes microtubules and promotes spindle bipolarity, independent of its chromatin remodeling function.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Ran GTPase (RanGTP) activates nuclear localization signal (NLS)-containing proteins to induce spindle assembly.
- Several NLS proteins are known spindle assembly factors, but additional factors are sought.
Purpose of the Study:
- To identify novel proteins involved in spindle assembly.
- To investigate the role of CHD4 in microtubule dynamics and spindle formation.
Main Methods:
- Immunodepletion experiments in Xenopus egg extracts.
- RNA interference (RNAi) in HeLa and Drosophila S2 cells.
- Analysis of microtubule (MT) stabilization and spindle organization.
Main Results:
- CHD4 identified as a RanGTP-dependent microtubule-associated protein (MAP).
- CHD4 depletion impairs MT production and spindle assembly.
- CHD4 stabilizes MTs and promotes bipolar spindle organization, independent of chromatin remodeling.
Conclusions:
- CHD4 functions as a novel MAP essential for MT stabilization.
- CHD4 plays a critical role in generating spindle bipolarity.
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