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In Vitro Bioluminescence Assay to Characterize Circadian Rhythm in Mammary Epithelial Cells
Published on: September 28, 2017
The polycomb group protein EZH2 is required for mammalian circadian clock function
Jean-Pierre Etchegaray1, Xiaoming Yang1, Jason P DeBruyne1
1Department of Neurobiology, University of Massachusetts Medical School, Worcester, Massachusetts 01605.
The Journal of Biological Chemistry
|May 24, 2006
Summary
Polycomb group proteins, specifically EZH2, are crucial for maintaining the mouse circadian clock. EZH2 regulates gene expression in the core clockwork, ensuring proper circadian rhythm function.
Area of Science:
- Chronobiology
- Epigenetics
- Molecular Biology
Background:
- The circadian clock mechanism relies on intricate molecular processes.
- Polycomb group proteins are known epigenetic regulators.
Purpose of the Study:
- To investigate the role of histone methylation by polycomb group proteins in the mammalian circadian clock.
- To determine the involvement of EZH2 in regulating circadian gene expression.
Main Methods:
- Co-immunoprecipitation assays to detect protein interactions.
- Chromatin immunoprecipitation to assess EZH2 binding and histone methylation.
- Overexpression and RNA interference studies in cell cultures.
Main Results:
- EZH2 (Enhancer of zeste homolog 2) was found to co-immunoprecipitate with CLOCK and BMAL1.
- EZH2 binds to and methylates H3K27 on the promoters of Period 1 and Period 2 genes.
- Disruption of EZH2 function impaired circadian rhythms in NIH 3T3 cells.
Conclusions:
- EZH2 plays a significant role in the maintenance of mammalian circadian rhythms.
- The activity of polycomb group proteins extends to the core molecular clockwork.
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