3ERT

HUMAN ESTROGEN RECEPTOR ALPHA LIGAND-BINDING DOMAIN IN COMPLEX WITH 4-HYDROXYTAMOXIFEN

• PDB DOI:  https://doi.org/10.2210/pdb3ERT/pdb
• Entry: 3ERT supersedes: 2ERT

• Classification: NUCLEAR RECEPTOR
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1999-03-30 Released: 1999-04-08 
• Deposition Author(s): Shiau, A.K., Barstad, D., Loria, P.M., Cheng, L., Kushner, P.J., Agard, D.A., Greene, G.L.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.262 
• R-Value Work: 0.229 

Literature

The structural basis of estrogen receptor/coactivator recognition and the antagonism of this interaction by tamoxifen.

Shiau, A.K., Barstad, D., Loria, P.M., Cheng, L., Kushner, P.J., Agard, D.A., Greene, G.L.

(1998) Cell 95: 927-937

• PubMed: 9875847 
• DOI: https://doi.org/10.1016/s0092-8674(00)81717-1
• Primary Citation of Related Structures:  
  3ERD, 3ERT


• PubMed Abstract: 
  

Ligand-dependent activation of transcription by nuclear receptors (NRs) is mediated by interactions with coactivators. Receptor agonists promote coactivator binding, and antagonists block coactivator binding. Here we report the crystal structure of the human estrogen receptor alpha (hER alpha) ligand-binding domain (LBD) bound to both the agonist diethylstilbestrol (DES) and a peptide derived from the NR box II region of the coactivator GRIP1 and the crystal structure of the hER alpha LBD bound to the selective antagonist 4-hydroxytamoxifen (OHT). In the DES-LBD-peptide complex, the peptide binds as a short alpha helix to a hydrophobic groove on the surface of the LBD. In the OHT-LBD complex, helix 12 occludes the coactivator recognition groove by mimicking the interactions of the NR box peptide with the LBD. These structures reveal the two distinct mechanisms by which structural features of OHT promote this "autoinhibitory" helix 12 conformation.

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Organizational Affiliation: 

Howard Hughes Medical Institute and the Department of Biochemistry and Biophysics, University of California at San Francisco, 94143-0448, USA.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 30.24 kDa 
• Atom Count: 2,070 
• Modelled Residue Count: 247 
• Deposited Residue Count: 261 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (ESTROGEN RECEPTOR ALPHA)	A	261	Homo sapiens	Mutation(s): 0  Gene Names: ESTROGEN RECEPTOR ALPHA, ESR1, ESR, NR3A1
UniProt & NIH Common Fund Data Resources
Find proteins for P03372 (Homo sapiens) Explore P03372  Go to UniProtKB:  P03372
PHAROS:  P03372

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
OHT	B [auth A]	4-HYDROXYTAMOXIFEN C26 H29 N O2 TXUZVZSFRXZGTL-QPLCGJKRSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
OHT	BindingDB:  3ERT	Ki: min: 0.04, max: 5.7 (nM) from 5 assay(s)
		IC50: min: 0.31, max: 40 (nM) from 11 assay(s)
		EC50: min: 6, max: 16 (nM) from 3 assay(s)
	PDBBind:  3ERT	Ki: 0.25 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.262 
• R-Value Work: 0.229 
• Space Group: P 6₅ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 58.242	α = 90
b = 58.242	β = 90
c = 277.467	γ = 120

Software Package:

Software Name	Purpose
AMoRE	phasing
X-PLOR	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 1999-04-08 
Deposition Author(s): Shiau, A.K., Barstad, D., Loria, P.M., Cheng, L., Kushner, P.J., Agard, D.A., Greene, G.L.
• This entry supersedes: 2ERT

Revision History  

• Version 1.0: 1999-04-08
  Type: Initial release
  
• Version 1.1: 2008-04-26
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2011-11-16
  Changes: Atomic model
• Version 1.4: 2023-09-06
  Changes: Data collection, Database references, Derived calculations, Refinement description