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Updated: Jun 22, 2026
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Prediction and Validation of Gene Regulatory Elements Activated During Retinoic Acid Induced Embryonic Stem Cell Differentiation
Published on: June 21, 2016
Steroid hormone receptors compete for factors that mediate their enhancer function
M E Meyer1, H Gronemeyer, B Turcotte
1Laboratoire de Génétique Moléculaire des Eucaryotes du CNRS, Strasbourg, France.
Cell
|May 5, 1989
Summary
Estrogen receptor (ER) inhibits progesterone receptor (PR) activity in HeLa cells. This cross-talk between hormone receptors suggests competition for essential transcription factors, impacting gene expression.
Area of Science:
- Molecular Endocrinology
- Gene Regulation
- Hormone Receptor Interactions
Background:
- The progesterone receptor (PR) and estrogen receptor (ER) are key nuclear receptors regulating gene transcription.
- Cross-talk between different nuclear receptors can influence cellular responses to hormones.
Purpose of the Study:
- To investigate the inhibitory effect of estrogen receptor (ER) on progesterone receptor (PR)-mediated gene transcription.
- To explore the mechanisms and extent of transcriptional interference between ER, PR, and glucocorticoid receptor (GR).
Main Methods:
- Transfection of HeLa cells with reporter genes and expression vectors for PR and ER.
- Co-expression studies to assess receptor interactions and transcriptional activity.
- Analysis of endogenous receptor interactions in breast cancer cell lines (T47D, MCF-7).
Main Results:
- ER significantly inhibited PR-stimulated reporter gene transcription in a dose- and estrogen-dependent manner.
- Both the N-terminal A/B region and hormone-binding domain of ER were implicated in the inhibition.
- ER also inhibited glucocorticoid receptor (GR) activity, and PR/GR inhibited ER activity.
- Transcriptional interference was observed between endogenous PR and ER in breast cancer cells, affecting pS2 gene expression.
Conclusions:
- Estrogen receptor (ER) actively interferes with progesterone receptor (PR) and glucocorticoid receptor (GR) transcriptional activity.
- The findings suggest that nuclear receptors may compete for limiting transcription factors, leading to cross-talk and modulation of gene expression.
- This receptor cross-talk has implications for understanding hormone-driven processes, particularly in breast cancer.
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