Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Protein Workshop | Ligand Explorer

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

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

Macromolecule Content

• Total Structure Weight: 42077.80 
• Atom Count: 2724 
• Residue Count: 353 
• Unique protein chains: 2

1UPK

Crystal structure of MO25 in complex with a C-terminal peptide of STRAD

• DOI: 10.2210/pdb1UPK/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli


• Deposited: 2003-10-07 Released: 2004-01-22 
• Deposition Author(s): Milburn, C.C., Boudeau, J., Deak, M., Alessi, D.R., Van Aalten, D.M.F.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.85 Å
• R-Value Free: 0.230 
• R-Value Work: 0.202 

Literature

Crystal Structure of Mo25 Alpha in Complex with the C-Terminus of the Pseudo Kinase Ste-20 Related Adaptor (Strad)

Milburn, C.C., Boudeau, J., Deak, M., Alessi, D.R., Van Aalten, D.M.F.

(2004) Nat.Struct.Mol.Biol. 11: 193

• PubMed: 14730349 
• DOI: 10.1038/nsmb716
• Primary Citation of Related Structures:  
  1UPL


• PubMed Abstract: 
  

Mouse protein 25 alpha (MO25 alpha) is a 40-kDa protein that, together with the STE20-related adaptor-alpha (STRAD alpha) pseudo kinase, forms a regulatory complex capable of stimulating the activity of the LKB1 tumor suppressor protein kinase. The latter is mutated in the inherited Peutz-Jeghers cancer syndrome (PJS). MO25 alpha binds directly to a conserved Trp-Glu-Phe sequence at the STRAD alpha C terminus, markedly enhancing binding of STRAD alpha to LKB1 and increasing LKB1 catalytic activity. The MO25 alpha crystal structure reveals a helical repeat fold, distantly related to the Armadillo proteins. A complex with the STRAD alpha peptide reveals a hydrophobic pocket that is involved in a unique and specific interaction with the Trp-Glu-Phe motif, further supported by mutagenesis studies. The data represent a first step toward structural analysis of the LKB1-STRAD-MO25 complex, and suggests that MO25 alpha is a scaffold protein to which other regions of STRAD-LKB1, cellular LKB1 substrates or regulatory components could bind.

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Organizational Affiliation: 

Division of Biological Chemistry & Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
MO25 PROTEIN	A	341	Homo sapiens	Mutation(s): 0  Gene Names: CAB39 (MO25)
Find proteins for Q9Y376 (Homo sapiens) Go to Gene View: CAB39 Go to UniProtKB:  Q9Y376

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
STE-20 RELATED ADAPTOR	B	12	Homo sapiens	Mutation(s): 0  Gene Names: STRADA (LYK5, STRAD)
Find proteins for Q7RTN6 (Homo sapiens) Go to Gene View: STRADA Go to UniProtKB:  Q7RTN6

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
MES	A	2-(N-MORPHOLINO)-ETHANESULFONIC ACID C6 H13 N O4 S SXGZJKUKBWWHRA-UHFFFAOYSA-N

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.85 Å
• R-Value Free: 0.230 
• R-Value Work: 0.202 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length (Å)	Angle (°)
a = 77.650	α = 90.00
b = 134.033	β = 90.00
c = 40.224	γ = 90.00

Software Package:

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

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2003-10-07 
• Released Date: 2004-01-22 
• Deposition Author(s): Milburn, C.C., Boudeau, J., Deak, M., Alessi, D.R., Van Aalten, D.M.F.

Revision History 

• Version 1.0: 2004-01-22
  Type: Initial release
• Version 1.1: 2011-05-08
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance