2J8Z

Crystal Structure of human P53 inducible oxidoreductase (TP53I3,PIG3)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.271 
  • R-Value Work: 0.226 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Three-Dimensional Structure and Enzymatic Function of Proapoptotic Human P53-Inducible Quinone Oxidoreductase Pig3.

Porte, S.Valencia, E.Yakovtseva, E.A.Borras, E.Shafqat, N.Debreczeny, J.E.Pike, A.C.W.Oppermann, U.Farres, J.Fita, I.Pares, X.

(2009) J.Biol.Chem. 284: 17194

  • DOI: 10.1074/jbc.M109.001800

  • PubMed Abstract: 
  • Tumor suppressor p53 regulates the expression of p53-induced genes (PIG) that trigger apoptosis. PIG3 or TP53I3 is the only known member of the medium chain dehydrogenase/reductase superfamily induced by p53 and is used as a proapoptotic marker. Alth ...

    Tumor suppressor p53 regulates the expression of p53-induced genes (PIG) that trigger apoptosis. PIG3 or TP53I3 is the only known member of the medium chain dehydrogenase/reductase superfamily induced by p53 and is used as a proapoptotic marker. Although the participation of PIG3 in the apoptotic pathway is proven, the protein and its mechanism of action were never characterized. We analyzed human PIG3 enzymatic function and found NADPH-dependent reductase activity with ortho-quinones, which is consistent with the classification of PIG3 in the quinone oxidoreductase family. However, the activity is much lower than that of zeta-crystallin, a better known quinone oxidoreductase. In addition, we report the crystallographic structure of PIG3, which allowed the identification of substrate- and cofactor-binding sites, with residues fully conserved from bacteria to human. Tyr-59 in zeta-crystallin (Tyr-51 in PIG3) was suggested to participate in the catalysis of quinone reduction. However, kinetics of Tyr/Phe and Tyr/Ala mutants of both enzymes demonstrated that the active site Tyr is not catalytic but may participate in substrate binding, consistent with a mechanism based on propinquity effects. It has been proposed that PIG3 contribution to apoptosis would be through oxidative stress generation. We found that in vitro activity and in vivo overexpression of PIG3 accumulate reactive oxygen species. Accordingly, an inactive PIG3 mutant (S151V) did not produce reactive oxygen species in cells, indicating that enzymatically active protein is necessary for this function. This supports that PIG3 action is through oxidative stress produced by its enzymatic activity and provides essential knowledge for eventual control of apoptosis.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
QUINONE OXIDOREDUCTASE
A
354Homo sapiensMutation(s): 0 
Gene Names: TP53I3 (PIG3)
EC: 1.-.-.-
Find proteins for Q53FA7 (Homo sapiens)
Go to Gene View: TP53I3
Go to UniProtKB:  Q53FA7
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAP
Query on NAP

Download SDF File 
Download CCD File 
A
NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE
2'-MONOPHOSPHOADENOSINE 5'-DIPHOSPHORIBOSE
C21 H28 N7 O17 P3
XJLXINKUBYWONI-NNYOXOHSSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.271 
  • R-Value Work: 0.226 
  • Space Group: P 43 2 2
Unit Cell:
Length (Å)Angle (°)
a = 46.860α = 90.00
b = 46.860β = 90.00
c = 315.930γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
XSCALEdata scaling
XDSdata reduction
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-11-06
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Version format compliance