4JDD image
Deposition Date 2013-02-25
Release Date 2013-05-15
Last Version Date 2024-10-30
Entry Detail
PDB ID:
4JDD
Title:
14-3-3 protein interaction with Estrogen Receptor Alpha provides a novel drug target interface
Biological Source:
Source Organism:
Homo sapiens (Taxon ID: 9606)
Host Organism:
Method Details:
Experimental Method:
Resolution:
2.10 Å
R-Value Free:
0.23
R-Value Work:
0.19
R-Value Observed:
0.19
Space Group:
C 2 2 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:14-3-3 protein sigma
Gene (Uniprot):SFN
Chain IDs:A
Chain Length:236
Number of Molecules:1
Biological Source:Homo sapiens
Polymer Type:polypeptide(L)
Molecule:Estrogen receptor Peptide
Gene (Uniprot):ESR1
Chain IDs:B
Chain Length:11
Number of Molecules:1
Biological Source:Homo sapiens
Modified Residue
Compound ID Chain ID Parent Comp ID Details 2D Image
TPO B THR PHOSPHOTHREONINE
Ligand Molecules
Primary Citation
Interaction of 14-3-3 proteins with the estrogen receptor alpha F domain provides a drug target interface.
Proc. Natl. Acad. Sci. U.S.A. 110 8894 8899 (2013)
PMID: 23676274 DOI: 10.1073/pnas.1220809110

Abstact

Estrogen receptor alpha (ERα) is involved in numerous physiological and pathological processes, including breast cancer. Breast cancer therapy is therefore currently directed at inhibiting the transcriptional potency of ERα, either by blocking estrogen production through aromatase inhibitors or antiestrogens that compete for hormone binding. Due to resistance, new treatment modalities are needed and as ERα dimerization is essential for its activity, interference with receptor dimerization offers a new opportunity to exploit in drug design. Here we describe a unique mechanism of how ERα dimerization is negatively controlled by interaction with 14-3-3 proteins at the extreme C terminus of the receptor. Moreover, the small-molecule fusicoccin (FC) stabilizes this ERα/14-3-3 interaction. Cocrystallization of the trimeric ERα/14-3-3/FC complex provides the structural basis for this stabilization and shows the importance of phosphorylation of the penultimate Threonine (ERα-T(594)) for high-affinity interaction. We confirm that T(594) is a distinct ERα phosphorylation site in the breast cancer cell line MCF-7 using a phospho-T(594)-specific antibody and by mass spectrometry. In line with its ERα/14-3-3 interaction stabilizing effect, fusicoccin reduces the estradiol-stimulated ERα dimerization, inhibits ERα/chromatin interactions and downstream gene expression, resulting in decreased cell proliferation. Herewith, a unique functional phosphosite and an alternative regulation mechanism of ERα are provided, together with a small molecule that selectively targets this ERα/14-3-3 interface.

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Primary Citation of related structures