Biological Assembly 1  

 3D View: Structure | Electron Density

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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: 33168.30 
• Atom Count: 2275 
• Residue Count: 292 
• Unique protein chains: 2

1R2B

Crystal structure of the BCL6 BTB domain complexed with a SMRT co-repressor peptide

• DOI: 10.2210/pdb1R2B/pdb

• Classification: TRANSCRIPTION
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): 3 


• Deposited: 2003-09-26 Released: 2003-12-23 
• Deposition Author(s): Ahmad, K.F., Melnick, A., Lax, S.A., Bouchard, D., Liu, J., Kiang, C.L., Mayer, S., Licht, J.D., Prive, G.G.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.2 Å
• R-Value Free: 0.267 
• R-Value Work: 0.227 

Literature

Mechanism of SMRT corepressor recruitment by the BCL6 BTB domain.

Ahmad, K.F., Melnick, A., Lax, S., Bouchard, D., Liu, J., Kiang, C.L., Mayer, S., Takahashi, S., Licht, J.D., Prive, G.G.

(2003) Mol.Cell 12: 1551-1564

• PubMed: 14690607 
• Primary Citation of Related Structures:  
  1R29, 1R28


• PubMed Abstract: 
  

BCL6 encodes a transcription factor that represses genes necessary for the terminal differentiation of lymphocytes within germinal centers, and the misregulated expression of this factor is strongly implicated in several types of B cell lymphoma. The homodimeric BTB domain of BCL6 (also known as the POZ domain) is required for the repression activity of the protein and interacts directly with the SMRT and N-CoR corepressors that are found within large multiprotein histone deacetylase-containing complexes. We have identified a 17 residue fragment from SMRT that binds to the BCL6 BTB domain, and determined the crystal structure of the complex to 2.2 A. Two SMRT fragments bind symmetrically to the BCL6 BTB homodimer and, in combination with biochemical and in vivo data, the structure provides insight into the basis of transcriptional repression by this critical B cell lymphoma protein.

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Organizational Affiliation: 

Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 2M9, Canada.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
B-cell lymphoma 6 protein	A, B	127	Homo sapiens	Mutation(s): 3  Gene Names: BCL6 (BCL5, LAZ3, ZBTB27, ZNF51)
Find proteins for P41182 (Homo sapiens) Go to Gene View: BCL6 Go to UniProtKB:  P41182

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
Nuclear receptor co-repressor 2	C, D	19	Homo sapiens	Mutation(s): 0  Gene Names: NCOR2 (CTG26)
Find proteins for Q9Y618 (Homo sapiens) Go to Gene View: NCOR2 Go to UniProtKB:  Q9Y618

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.2 Å
• R-Value Free: 0.267 
• R-Value Work: 0.227 
• Space Group: P 1 2₁ 1

Unit Cell:

Length (Å)	Angle (°)
a = 54.228	α = 90.00
b = 38.543	β = 92.92
c = 76.659	γ = 90.00

Software Package:

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

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2003-09-26 
• Released Date: 2003-12-23 
• Deposition Author(s): Ahmad, K.F., Melnick, A., Lax, S.A., Bouchard, D., Liu, J., Kiang, C.L., Mayer, S., Licht, J.D., Prive, G.G.

Revision History 

• Version 1.0: 2003-12-23
  Type: Initial release
• Version 1.1: 2008-04-29
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance