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Updated: Jun 30, 2026
12:19
Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
AP-1 in cell proliferation and survival
1Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, California, CA 92093-0636, USA.
Oncogene
|June 13, 2001
Summary
Activating transcription factor 1 (AP-1) proteins regulate cell proliferation and apoptosis by controlling cell cycle genes. c-Jun promotes proliferation, while JunB suppresses it, impacting tumor suppressor p53.
Area of Science:
- Molecular Biology
- Cell Biology
- Genetics
Background:
- Activating transcription factor 1 (AP-1) dimers, composed of Jun, Fos, and ATF subgroups, are activated by various stimuli.
- AP-1 proteins are crucial DNA-binding transcription factors involved in cellular processes.
Purpose of the Study:
- To elucidate the physiological functions of AP-1 proteins in controlling cell proliferation, neoplastic transformation, and apoptosis.
- To identify target genes mediating AP-1's effects on cell life and death.
Main Methods:
- Studies utilizing cells and mice deficient in individual AP-1 proteins.
- Analysis of AP-1's regulation of cell cycle regulators and tumor suppressor genes.
Main Results:
- AP-1 proteins, particularly Jun family members, regulate cell fate by modulating cell cycle regulators like Cyclin D1, p53, p21, p19, and p16.
- c-Jun promotes cell proliferation by repressing tumor suppressor genes and inducing Cyclin D1.
- JunB antagonizes c-Jun by upregulating tumor suppressor genes and repressing Cyclin D1.
Conclusions:
- AP-1 proteins play a critical role in cell proliferation and apoptosis.
- The balance between c-Jun and JunB dictates cell fate, influencing tumor suppressor p53 activity and expression.
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