Biological Assembly 1  

 3D View: Structure | Electron Density

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Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - AB 

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

Macromolecule Content

• Total Structure Weight: 64258.73 
• Atom Count: 4195 
• Residue Count: 585 
• Unique protein chains: 2

1V18

The crystal structure of beta-catenin armadillo repeat complexed with a phosphorylated APC 20mer repeat.

• DOI: 10.2210/pdb1V18/pdb

• Classification: SIGNALING PROTEIN
• Organism(s): Homo sapiens, Mus musculus
• Expression System: Escherichia coli BL21


• Deposited: 2004-04-09 Released: 2005-01-12 
• Deposition Author(s): Ha, N.-C., Weis, W.I.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.1 Å
• R-Value Free: 0.253 
• R-Value Work: 0.207 

Literature

Mechanism of Phosphorylation-Dependent Binding of Apc to Beta-Catenin and its Role in Beta-Catenin Degradation

Ha, N.-C., Tonozuka, T., Stamos, J.L., Weis, W.I.

(2004) Mol.Cell 15: 511

• PubMed: 15327768 
• DOI: 10.1016/j.molcel.2004.08.010
• Primary Citation of Related Structures:  
  1T08


• PubMed Abstract: 
  

The transcriptional coactivator beta-catenin mediates Wnt growth factor signaling. In the absence of a Wnt signal, casein kinase 1 (CK1) and glycogen synthase kinase-3beta (GSK-3beta) phosphorylate cytosolic beta-catenin, thereby flagging it for recognition and destruction by the ubiquitin/proteosome machinery. Phosphorylation occurs in a multiprotein complex that includes the kinases, beta-catenin, axin, and the Adenomatous Polyposis Coli (APC) protein. The role of APC in this process is poorly understood. CK1epsilon and GSK-3beta phosphorylate APC, which increases its affinity for beta-catenin. Crystal structures of phosphorylated and nonphosphorylated APC bound to beta-catenin reveal a phosphorylation-dependent binding motif generated by mutual priming of CK1 and GSK-3beta substrate sequences. Axin is shown to act as a scaffold for substrate phosphorylation by these kinases. Phosphorylated APC and axin bind to the same surface of, and compete directly for, beta-catenin. The structural and biochemical data suggest a novel model for how APC functions in beta-catenin degradation.

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Organizational Affiliation: 

Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94043, USA.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
BETA-CATENIN	A	538	Mus musculus	Mutation(s): 0  Gene Names: Ctnnb1 (Catnb)
Find proteins for Q02248 (Mus musculus) Go to UniProtKB:  Q02248

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
ADENOMATOUS POLYPOSIS COLI	B	47	Homo sapiens	Mutation(s): 0  Gene Names: APC (DP2.5)
Find proteins for P25054 (Homo sapiens) Go to Gene View: APC Go to UniProtKB:  P25054

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
SEP	B	L-PEPTIDE LINKING	C3 H8 N O6 P		SER

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.1 Å
• R-Value Free: 0.253 
• R-Value Work: 0.207 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length (Å)	Angle (°)
a = 50.830	α = 90.00
b = 90.060	β = 90.00
c = 122.810	γ = 90.00

Software Package:

Software Name	Purpose
CNS	refinement
HKL-2000	data scaling
AMoRE	phasing
HKL-2000	data reduction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2004-04-09 
• Released Date: 2005-01-12 
• Deposition Author(s): Ha, N.-C., Weis, W.I.

Revision History 

• Version 1.0: 2005-01-12
  Type: Initial release
• Version 1.1: 2011-05-08
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance