Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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

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

Macromolecule Content

• Total Structure Weight: 34.00 kDa 
• Atom Count: 2304 
• Residue Count: 266 
• Unique protein chains: 1

4I5J

PP2A PR70 Holoenzyme

• DOI: 10.2210/pdb4I5J/pdb

• Classification: HYDROLASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2012-11-28 Released: 2013-05-08 
• Deposition Author(s): Xing, Y., Jeffery, P.D., Shi, Y.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.09 Å
• R-Value Free: 0.252 
• R-Value Work: 0.194 
• R-Value Observed: 0.197 

Literature

Structure of the Ca(2+)-dependent PP2A heterotrimer and insights into Cdc6 dephosphorylation.

Wlodarchak, N., Guo, F., Satyshur, K.A., Jiang, L., Jeffrey, P.D., Sun, T., Stanevich, V., Mumby, M.C., Xing, Y.

(2013) Cell Res 23: 931-946

• PubMed: 23752926 
• DOI: 10.1038/cr.2013.77
• Primary Citation of Related Structures:  
  4I5J, 4I5K, 4I5L, 4I5N


• PubMed Abstract: 
  

The B″/PR72 family of protein phosphatase 2A (PP2A) is an important PP2A family involved in diverse cellular processes, and uniquely regulated by calcium binding to the regulatory subunit. The PR70 subunit in this family interacts with cell division control 6 (Cdc6), a cell cycle regulator important for control of DNA replication. Here, we report crystal structures of the isolated PR72 and the trimeric PR70 holoenzyme at a resolution of 2.1 and 2.4 Å, respectively, and in vitro characterization of Cdc6 dephosphorylation. The holoenzyme structure reveals that one of the PR70 calcium-binding motifs directly contacts the scaffold subunit, resulting in the most compact scaffold subunit conformation among all PP2A holoenzymes. PR70 also binds distinctively to the catalytic subunit near the active site, which is required for PR70 to enhance phosphatase activity toward Cdc6. Our studies provide a structural basis for unique regulation of B″/PR72 holoenzymes by calcium ions, and suggest the mechanisms for precise control of substrate specificity among PP2A holoenzymes.

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Organizational Affiliation: 

McArdle Laboratory, Department of Oncology, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Serine/threonine-protein phosphatase 2A regulatory subunit B'' subunit alpha	A	285	Homo sapiens	Mutation(s): 0  Gene Names: PPP2R3A, PPP2R3
Find proteins for Q06190 (Homo sapiens) Explore Q06190  Go to UniProtKB:  Q06190
NIH Common Fund Data Resources
PHAROS:  Q06190 GTEx:  ENSG00000073711

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CA	A	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.09 Å
• R-Value Free: 0.252 
• R-Value Work: 0.194 
• R-Value Observed: 0.197 
• Space Group: P 3₁ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 67.61	α = 90
b = 67.61	β = 90
c = 139.11	γ = 120

Software Package:

Software Name	Purpose
PHENIX	refinement
CNS	refinement
CBASS	data collection
DENZO	data reduction
SCALEPACK	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2012-11-28 
• Released Date: 2013-05-08 
Deposition Author(s): Xing, Y., Jeffery, P.D., Shi, Y.

Revision History 

• Version 1.0: 2013-05-08
  Type: Initial release
  
• Version 1.1: 2013-07-24
  Changes: Database references
• Version 1.2: 2019-07-17
  Changes: Data collection, Refinement description