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Updated: Jul 12, 2026
10:36
Systems Biology of Metabolic Regulation by Estrogen Receptor Signaling in Breast Cancer
Published on: March 17, 2016
Response element sequence modulates estrogen receptor alpha and beta affinity and activity.
P C Kulakosky1, M A McCarty, S C Jernigan
1Department of Biochemistry and Molecular Biology, University of Louisville School of Medicine, Louisville, Kentucky 40292, USA.
Journal of Molecular Endocrinology
|August 30, 2002
Summary
Altering estrogen receptor (ER)-estrogen response element (ERE) binding sites impacts gene transcription. Modifying ERE palindrome length significantly affects ER binding affinity and estradiol-induced transcription, with ERalpha showing stronger responses than ERbeta.
Area of Science:
- Molecular Biology
- Endocrinology
- Genetics
Background:
- Estrogen receptors (ERs) regulate gene expression through binding to estrogen response elements (EREs).
- The quantitative relationship between ER-ERE binding affinity and transcriptional activity is not fully understood.
- Estradiol (E2) is a key hormone mediating these effects.
Purpose of the Study:
- To systematically investigate how estrogen response element (ERE) palindrome length and flanking sequences influence ERalpha and ERbeta binding affinity.
- To determine the impact of these structural variations on estradiol (E2)-induced transcriptional activity.
- To compare the responses of ERalpha and ERbeta to these modifications.
Main Methods:
- In vitro binding assays to measure ERalpha and ERbeta affinity for various ERE sequences.
- Reporter gene assays in transfected cells to assess transcriptional induction.
- Analysis of ERE palindrome length and 3' flanking sequences.
Main Results:
- Increasing ERE palindrome length from 13 bp to 15 bp significantly enhanced ERalpha and ERbeta binding affinity and transcriptional activity.
- AT-rich flanking sequences had minimal impact on ER binding affinity or reporter gene activity.
- ERalpha generally exhibited higher binding affinity (lower Kd) and transcriptional induction compared to ERbeta.
- ERalpha showed a stronger correlation between ERE palindrome length and transcriptional induction than ERbeta.
- ERalpha also demonstrated a better correlation between ER-ERE Kd and transcriptional induction.
Conclusions:
- ERE palindrome length is a critical determinant of ER binding affinity and transcriptional regulation.
- ERalpha and ERbeta exhibit distinct binding and transcriptional properties.
- The findings provide quantitative insights into the structure-function relationship of ER-ERE interactions and their role in hormone-mediated gene expression.
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