1B3U | pdb_00001b3u

CRYSTAL STRUCTURE OF CONSTANT REGULATORY DOMAIN OF HUMAN PP2A, PR65ALPHA

• PDB DOI: https://doi.org/10.2210/pdb1B3U/pdb

• Classification: SCAFFOLD PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1998-12-14 Released: 1999-04-12 
• Deposition Author(s): Groves, M.R., Hanlon, N., Turowski, P., Hemmings, B., Barford, D.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 
  0.268 (Depositor), 0.265 (DCC) 
• R-Value Work: 
  0.209 (Depositor), 0.206 (DCC) 

Literature

The structure of the protein phosphatase 2A PR65/A subunit reveals the conformation of its 15 tandemly repeated HEAT motifs.

Groves, M.R., Hanlon, N., Turowski, P., Hemmings, B.A., Barford, D.

(1999) Cell 96: 99-110

• PubMed: 9989501 
• DOI: https://doi.org/10.1016/s0092-8674(00)80963-0
• Primary Citation Related Structures: 
  1B3U


• PubMed Abstract: 
  

  The PR65/A subunit of protein phosphatase 2A serves as a scaffolding molecule to coordinate the assembly of the catalytic subunit and a variable regulatory B subunit, generating functionally diverse heterotrimers. Mutations of the beta isoform of PR65 are associated with lung and colon tumors. The crystal structure of the PR65/Aalpha subunit, at 2.3 A resolution, reveals the conformation of its 15 tandemly repeated HEAT sequences, degenerate motifs of approximately 39 amino acids present in a variety of proteins, including huntingtin and importin beta. Individual motifs are composed of a pair of antiparallel alpha helices that assemble in a mainly linear, repetitive fashion to form an elongated molecule characterized by a double layer of alpha helices. Left-handed rotations at three interrepeat interfaces generate a novel left-hand superhelical conformation. The protein interaction interface is formed from the intrarepeat turns that are aligned to form a continuous ridge.

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Organizational Affiliation: 
• Department of Biochemistry, University of Oxford, United Kingdom.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Biological Assembly 2  

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

Biological assembly 2 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 130.49 kDa 
• Atom Count: 9,869 
• Modeled Residue Count: 1,176 
• Deposited Residue Count: 1,176 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (PROTEIN PHOSPHATASE PP2A)	A, B	588	Homo sapiens	Mutation(s): 0
UniProt & NIH Common Fund Data Resources
Find proteins for P30153 (Homo sapiens) Explore P30153  Go to UniProtKB:  P30153
PHAROS:  P30153 GTEx:  ENSG00000105568

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free:  0.268 (Depositor), 0.265 (DCC) 
• R-Value Work:  0.209 (Depositor), 0.206 (DCC) 

Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 64.28	α = 90
b = 112.15	β = 95.6
c = 122.63	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
DENZO	data reduction
CCP4	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 1999-04-12 
Deposition Author(s): Groves, M.R., Hanlon, N., Turowski, P., Hemmings, B., Barford, D.

Revision History  

• Version 1.0: 1999-04-12
  Type: Initial release
  
• Version 1.1: 2008-04-26
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2023-12-27
  Changes: Data collection, Database references