Related Experiment Video
Updated: Aug 14, 2026

Detecting the Ligand-binding Domain Dimerization Activity of Estrogen Receptor Alpha Using the Mammalian Two-Hybrid Assay
Published on: December 19, 2018
Repressive domain of unliganded human estrogen receptor alpha associates with Hsc70
Satoko Ogawa1, Hajime Oishi, Yoshihiro Mezaki
1The Institute of Molecular and Cellular Biosciences, University of Tokyo, Bunkyo-ku, Japan.
Abstract:
Estrogen receptor (ER) is a hormone-inducible transcription factor as a member of the nuclear receptor gene superfamily. Unliganded ER is transcriptionally silent and capable of DNA binding; however, it is unable to suppress the basal activity of the target gene promoters, unlike non-steroid hormone receptors that associate with corepressors in the absence of their cognate ligands. To study the molecular basis of how unliganded human ERalpha is maintained silent in gene regulation upon the target gene promoters, we biochemically searched interactants for hERalpha, and identified heat shock protein 70 (Hsc70). Hsc70 appeared to associate with the N-terminal hormone binding E domain, that also turned out a transcriptionally repressive domain. Competitive association of Hsc70 with a best known coactivator p300 was observed. Thus, these findings suggest that Hsc70 associates with unliganded hERalpha, and thereby deters hERalpha from recruiting transcriptional coregulators, presumably as a component of chaperone complexes.
More Related Videos
11:07Biochemical Reconstitution of Steroid Receptor•Hsp90 Protein Complexes and Reactivation of Ligand Binding
Published on: September 21, 2011
10:51Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists
Published on: November 15, 2013
Related Concept Videos
Export of Misfolded Proteins out of the ER
Regulation of the Unfolded Protein Response
The Unfolded Protein Response
Regulation of Nuclear Protein Sorting
Directing Proteins to the Rough Endoplasmic Reticulum
Receptor Downregulation in MVBs
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...