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Updated: Jun 23, 2026
05:35
Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins
Published on: March 3, 2016
HAUS, the 8-subunit human Augmin complex, regulates centrosome and spindle integrity
Steffen Lawo1, Mikhail Bashkurov, Michael Mullin
1Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada.
Current Biology : CB
|May 12, 2009
Summary
The human Augmin complex (HAUS) is crucial for maintaining centrosome and spindle integrity during cell division. Its disruption leads to severe mitotic defects, highlighting its role in accurate chromosome segregation.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Accurate chromosome segregation relies on a robust microtubule-based mitotic spindle.
- Spindle assembly involves centrosomes, microtubules, molecular motors, and nonmotor proteins.
Purpose of the Study:
- Identify novel regulators of mitotic spindle assembly using an RNA-interference screen of the human centrosome proteome.
- Investigate the function of the HAUS complex in centrosome and spindle integrity.
Main Methods:
- RNA-interference screen of the human centrosome proteome.
- Localization studies of the HAUS complex.
- Analysis of mitotic defects upon HAUS disruption, including centrosome morphology, spindle formation, and kinetochore microtubule stability.
- Codepletion experiments with NuMA to assess functional interactions.
Main Results:
- Identified HAUS, an 8-subunit complex homologous to Drosophila Augmin, as a novel spindle assembly regulator.
- HAUS localizes to centrosomes and spindle microtubules; its disruption causes centrosome fragmentation and enlargement.
- HAUS disruption leads to kinetochore microtubule destabilization and multipolar spindle formation.
- Mitotic defects are rescued by NuMA codepletion, suggesting opposing activities and altered NuMA localization upon HAUS disruption.
Conclusions:
- The human Augmin complex (HAUS) is essential for regulating centrosome and spindle integrity.
- HAUS is a critical and evolutionarily conserved multisubunit protein complex.
- HAUS functions in conjunction with NuMA to ensure proper mitotic progression.
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