Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 28.38 kDa 
• Atom Count: 2038 
• Residue Count: 241 
• Unique protein chains: 2

4JDD

14-3-3 protein interaction with Estrogen Receptor Alpha provides a novel drug target interface

• DOI: 10.2210/pdb4JDD/pdb

• Classification: SIGNALING PROTEIN/Peptide
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2013-02-25 Released: 2013-05-15 
• Deposition Author(s): Bier, D., Ottmann, C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free: 0.232 
• R-Value Work: 0.192 
• R-Value Observed: 0.194 

Literature

Interaction of 14-3-3 proteins with the estrogen receptor alpha F domain provides a drug target interface.

De Vries-van Leeuwen, I.J., da Costa Pereira, D., Flach, K.D., Piersma, S.R., Haase, C., Bier, D., Yalcin, Z., Michalides, R., Feenstra, K.A., Jimenez, C.R., de Greef, T.F., Brunsveld, L., Ottmann, C., Zwart, W., de Boer, A.H.

(2013) Proc Natl Acad Sci U S A 110: 8894-8899

• PubMed: 23676274 
• DOI: 10.1073/pnas.1220809110
• Primary Citation of Related Structures:  
  4JC3, 4JDD


• PubMed Abstract: 
  

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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Organizational Affiliation: 

Department of Structural Biology, Faculty Earth and Life Sciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
14-3-3 protein sigma	A	236	Homo sapiens	Mutation(s): 0  Gene Names: HME1, NM_006142, SFN
Find proteins for P31947 (Homo sapiens) Explore P31947  Go to UniProtKB:  P31947
NIH Common Fund Data Resources
PHAROS  P31947 GTEx  ENSG00000175793

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Estrogen receptor Peptide	B	11	Homo sapiens	Mutation(s): 0  Gene Names: ESR1, ESR, NR3A1
Find proteins for P03372 (Homo sapiens) Explore P03372  Go to UniProtKB:  P03372
NIH Common Fund Data Resources
PHAROS  P03372 GTEx  ENSG00000091831

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
FSC	A	FUSICOCCIN C36 H56 O12 KXTYBXCEQOANSX-WYKQKOHHSA-N

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
TPO	B	L-PEPTIDE LINKING	C4 H10 N O6 P		THR

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free: 0.232 
• R-Value Work: 0.192 
• R-Value Observed: 0.194 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 82.49	α = 90
b = 111.43	β = 90
c = 62.24	γ = 90

Software Package:

Software Name	Purpose
XSCALE	data scaling
PHASER	phasing
REFMAC	refinement
PDB_EXTRACT	data extraction
MAR345dtb	data collection
XDS	data reduction
XDS	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2013-02-25 
• Released Date: 2013-05-15 
Deposition Author(s): Bier, D., Ottmann, C.

Revision History 

• Version 1.0: 2013-05-15
  Type: Initial release
  
• Version 1.1: 2017-06-07
  Changes: Database references