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Updated: Jul 26, 2026
12:19
Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
Functional antagonism between E2F family members.
M V Frolov1, D S Huen, O Stevaux
1Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts 02129, USA.
Genes & Development
|August 21, 2001
Summary
In Drosophila, two E2F genes, de2f1 and de2f2, have opposing roles in development. dE2F1 activates transcription, while dE2F2 represses it, with their interaction controlling cell proliferation.
Area of Science:
- Developmental Biology
- Molecular Biology
- Genetics
Background:
- E2F transcription factors regulate cell cycle control through diverse family members.
- Mammalian cells possess numerous E2F genes, whereas Drosophila has only two: de2f1 and de2f2.
Purpose of the Study:
- To investigate the distinct regulatory roles and opposing functions of de2f1 and de2f2 during Drosophila development.
- To elucidate how these two E2F proteins interact to control gene expression and cell proliferation.
Main Methods:
- Analyzing the functions of de2f1 and de2f2 in Drosophila.
- Studying gene expression patterns and DNA synthesis in wild-type and mutant embryos.
- Utilizing genetic mutations, including de2f1 and de2f2 single and double mutants.
Main Results:
- dE2F1 acts as a transcriptional activator, and its loss reduces E2F-regulated gene expression and cell proliferation.
- dE2F2 functions as a transcriptional repressor, with its loss leading to increased and expanded gene expression.
- de2f1 mutant phenotypes are largely due to dE2F2 activity and can be suppressed by de2f2 mutations.
- Absence of both dE2F1 and dE2F2 allows for relatively normal DNA synthesis patterns in eye discs.
Conclusions:
- Drosophila utilizes distinct activator (dE2F1) and repressor (dE2F2) E2F proteins to pattern transcription during development.
- The interplay between these antagonistic E2F complexes determines the net effect on cell proliferation.
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