Estrogen Receptor-Mediated Transcription In Vitro

Abstract

Estrogen receptor (ER) is a ligand-activated transcription activator. To elucidate the mechanism of ER-mediated transcription in detail, we studied transcriptional activity of the ER in vitro. We demonstrated ER-mediated transcription in a cell-free transcription system is ligand-dependent. Antiestrogens ICI182,,384, ICI182,780 and 4-hydroxytamoxifen significantly inhibited transcriptional activity of the ER. Estradiol overcame the inhibitory effect of the antiestrogens and induced ER-mediated transcription. Under the condition used for transcription assays, ICI164, 384, ICI182, 780 inhibited ER-ERE complex formation which might contribute to the inhibitory effect of these antiestrogens on ER-mediated transcription. 4-hydroxytamoxifen changed the mobility of ER-ERE complex in the gel mobility shift assay, suggesting a conformational change of the complex. Steroid receptor coactivator 1 (SRC-1) significantly augmented ER-mediated-transcription in vitro. The hormone binding domain (HBD) of the ER that binds to estrogen receptor associated proteins (ERAPs) in a ligand-dependent manner inhibited ER-mediated transcription in vitro.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1999
Accession Number
ADA381241

Entities

People

  • Hong Liu
  • Virgil C. Jordan

Organizations

  • Northwestern University

Tags

DTIC Thesaurus Topics

  • Amino Acids
  • Breast Cancer
  • Cell Physiological Processes
  • Cells
  • Chemistry
  • Contrast
  • Crystal Structure
  • Estrogens
  • Gene Expression
  • Health Services
  • Hormones
  • Materials
  • Mobility
  • Molecular Dynamics
  • Neoplasms
  • Proteins
  • United States

Fields of Study

  • Biology

Readers

  • Breast cancer cell signaling and growth regulation.