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Published on: June 6, 2017
A complex with chromatin modifiers that occupies E2F- and Myc-responsive genes in G0 cells
Hidesato Ogawa1, Kei-Ichiro Ishiguro, Stefan Gaubatz
1Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA 02115, USA.
Science (New York, N.Y.)
|May 11, 2002
Summary
E2F-6 protein complexes silence genes via chromatin modifiers in quiescent cells. This mechanism involves histone modifications and Polycomb group proteins, independent of retinoblastoma proteins.
Area of Science:
- Molecular Biology
- Epigenetics
- Cell Cycle Regulation
Background:
- E2F-6 is a transcription factor involved in gene silencing.
- Its repression mechanism, independent of retinoblastoma proteins, requires further elucidation.
Purpose of the Study:
- To purify and characterize the E2F-6 protein complex.
- To understand the molecular mechanisms underlying E2F-6-mediated gene silencing.
Main Methods:
- Purification of the E2F-6 complex from cultured cells.
- Identification of associated proteins and chromatin modifiers.
- Analysis of target promoter occupancy in different cell cycle phases.
Main Results:
- E2F-6 forms a multimeric complex with Mga and Max, binding to E2F, Myc, and Brachyury sites.
- The complex contains novel histone methyltransferase (H3K9), HP1gamma, and Polycomb group proteins.
- E2F-6 complex preferentially binds target promoters in G0 (quiescent) cells over G1 cells.
Conclusions:
- Chromatin modifiers within the E2F-6 complex mediate gene silencing.
- This silencing affects E2F- and Myc-responsive genes in quiescent cells.
- E2F-6 plays a significant role in cell cycle-dependent gene regulation through epigenetic mechanisms.
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