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: 59852.84 
• Atom Count: 3710 
• Residue Count: 528 
• Unique protein chains: 2

4WRQ

Crystal Structure of 14-3-3 zeta with Chibby peptide

• DOI: 10.2210/pdb4WRQ/pdb

• Classification: SIGNALING PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)


• Deposited: 2014-10-24 Released: 2015-05-06 
• Deposition Author(s): Killoran, R.C., Shilton, B.H., Choy, W.Y.
• Funding Organization(s): Canadian Institutes of Health Research 

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.409 Å
• R-Value Free: 0.256 
• R-Value Work: 0.203 

Literature

Structural Analysis of the 14-3-3 zeta /Chibby Interaction Involved in Wnt/ beta-Catenin Signaling.

Killoran, R.C., Fan, J., Yang, D., Shilton, B.H., Choy, W.Y.

(2015) Plos One 10: e0123934-e0123934

• PubMed: 25909186 
• DOI: 10.1371/journal.pone.0123934


• PubMed Abstract: 
  

The partially disordered Chibby (Cby) is a conserved nuclear protein that antagonizes the Wnt/β-catenin signaling pathway. By competing with the Tcf/Lef family proteins for binding to β-catenin, Cby abrogates the β-catenin-mediated transcription of Wnt signaling genes. Additionally, upon phosphorylation on S20 by the kinase Akt, Cby forms a complex with 14-3-3 to facilitate the nuclear export of β-catenin, which represents another crucial mechanism for the regulation of Wnt signaling. To obtain a mechanistic understanding of the 14-3-3/Cby interaction, we have extensively characterized the complex using X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and isothermal titration calorimetry (ITC). The crystal structure of the human 14-3-3ζ/Cby protein-peptide complex reveals a canonical binding mode; however the residue at the +2 position from the phosphorylated serine is shown to be uniquely oriented relative to other solved structures of 14-3-3 complexes. Our ITC results illustrate that although the phosphorylation of S20 is essential for Cby to recognize 14-3-3, residues flanking the phosphorylation site also contribute to the binding affinity. However, as is commonly observed in other 14-3-3/phosphopeptide crystal structures, residues of Cby flanking the 14-3-3 binding motif lack observable electron density. To obtain a more detailed binding interface, we have completed the backbone NMR resonance assignment of 14-3-3ζ. NMR titration experiments reveal that residues outside of the 14-3-3 conserved binding cleft, namely a flexible loop consisting of residues 203-210, are also involved in binding Cby. By using a combined X-ray and NMR approach, we have dissected the molecular basis of the 14-3-3/Cby interaction.

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Organizational Affiliation: 

Department of Biochemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
14-3-3 protein zeta/delta	A, B	246	Homo sapiens	Mutation(s): 0  Gene Names: YWHAZ
Find proteins for P63104 (Homo sapiens) Go to Gene View: YWHAZ Go to UniProtKB:  P63104

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
Chibby	C, D	18	Homo sapiens	Mutation(s): 0  Gene Names: CBY1 (ARB1, C22orf2, CBY, PGEA1)
Find proteins for Q9Y3M2 (Homo sapiens) Go to Gene View: CBY1 Go to UniProtKB:  Q9Y3M2

Small Molecules

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

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.409 Å
• R-Value Free: 0.256 
• R-Value Work: 0.203 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length (Å)	Angle (°)
a = 70.830	α = 90.00
b = 71.960	β = 90.00
c = 130.990	γ = 90.00

Software Package:

Software Name	Purpose
PDB_EXTRACT	data extraction
PHENIX	refinement

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2014-10-24 
• Released Date: 2015-05-06 
• Deposition Author(s): Killoran, R.C., Shilton, B.H., Choy, W.Y.

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Funding Organization	Location	Grant Number
Canadian Institutes of Health Research	Canada	MOP 74679

Revision History 

• Version 1.0: 2015-05-06
  Type: Initial release
• Version 1.1: 2017-09-13
  Type: Author supporting evidence, Derived calculations, Other, Source and taxonomy, Structure summary