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Published on: December 31, 2014
Over-expression of FoxM1 stimulates cyclin B1 expression
T W Leung1, S S Lin, A C Tsang
1Department of Biochemistry, Faculty of Medicine, University of Hong Kong, China.
FEBS Letters
|October 30, 2001
Summary
Forkhead box M1 (FoxM1) is crucial for cell cycle progression. This study shows FoxM1 directly activates cyclin B1 expression, impacting cell growth recovery and S-M phase coupling.
Area of Science:
- Molecular Biology
- Cell Biology
- Genetics
Background:
- FoxM1 is a transcription factor essential for proliferating cells.
- FoxM1 plays a role in cell cycle progression, specifically S-M phase coupling.
- Its precise regulatory targets and mechanisms require further elucidation.
Purpose of the Study:
- To investigate the regulatory role of FoxM1 in cell cycle progression.
- To identify downstream targets regulated by FoxM1.
- To determine if FoxM1 directly activates specific cyclin promoters.
Main Methods:
- Establishment of doxycycline-inducible FoxM1 expression in HeLa cells.
- Flow cytometry, Western blot, and Northern blot analyses to quantify protein and RNA levels.
- Transient reporter assays to assess promoter activity.
Main Results:
- Overexpression of FoxM1 enhanced growth recovery after serum starvation.
- Elevated FoxM1 levels specifically stimulated cyclin B1 expression, not cyclin D1.
- FoxM1 was shown to activate the cyclin B1 promoter.
Conclusions:
- FoxM1 is a key regulator of cyclin B1 expression.
- FoxM1-mediated activation of cyclin B1 contributes to cell cycle progression and growth recovery.
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