Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly 2  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 57.46 kDa 
• Atom Count: 4051 
• Modelled Residue Count: 478 
• Deposited Residue Count: 496 
• Unique protein chains: 1

1PK5

Crystal structure of the orphan nuclear receptor LRH-1

• PDB DOI: 10.2210/pdb1PK5/pdb

• Classification: GENE REGULATION
• Organism(s): Mus musculus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2003-06-04 Released: 2003-07-01 
• Deposition Author(s): Sablin, E.P., Krylova, I.N., Fletterick, R.J., Ingraham, H.A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 0.235 
• R-Value Work: 0.208 
• R-Value Observed: 0.208 

Literature

Structural basis for ligand-independent activation of the orphan nuclear receptor LRH-1

Sablin, E.P., Krylova, I.N., Fletterick, R.J., Ingraham, H.A.

(2003) Mol Cell 11: 1575-1585

• PubMed: 12820970 
• DOI: 10.1016/s1097-2765(03)00236-3
• Primary Citation of Related Structures:  
  1PK5


• PubMed Abstract: 
  

The orphan nuclear receptors SF-1 and LRH-1 are constitutively active, but it remains uncertain whether their activation is hormone dependent. We report the crystal structure of the LRH-1 ligand binding domain to 2.4 A resolution and find the receptor to be a monomer that adopts an active conformation with a large but empty hydrophobic pocket. Adding bulky side chains into this pocket resulted in full or greater activity suggesting that, while LRH-1 could accommodate potential ligands, these are dispensable for basal activity. Constitutive LRH-1 activity appears to be conferred by a distinct structural element consisting of an extended helix 2 that provides an additional layer to the canonical LBD fold. Mutating the conserved arginine in helix 2 reduced LRH-1 receptor activity and coregulator recruitment, consistent with the partial loss-of-function phenotype exhibited by an analogous SF-1 human mutant. These findings illustrate an alternative structural strategy for nuclear receptor stabilization in the absence of ligand binding.

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Organizational Affiliation: 

Department of Biochemistry and Biophysics, University of California-San Francisco, San Francisco, CA 94143, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Orphan nuclear receptor NR5A2	A, B	248	Mus musculus	Mutation(s): 0  Gene Names: NR5A2 OR LRH1, Nr5a2, Lrh1
UniProt
Find proteins for P45448 (Mus musculus) Explore P45448  Go to UniProtKB:  P45448

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 0.235 
• R-Value Work: 0.208 
• R-Value Observed: 0.208 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 34.775	α = 90
b = 127.542	β = 91.72
c = 53.213	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2003-06-04 
• Released Date: 2003-07-01 
Deposition Author(s): Sablin, E.P., Krylova, I.N., Fletterick, R.J., Ingraham, H.A.

Revision History  

• Version 1.0: 2003-07-01
  Type: Initial release
  
• Version 1.1: 2008-04-29
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance