1I3P

THE 3.1 ANGSTROM RESOLUTION CRYSTAL STRUCTURE OF A MUTATED BACULOVIRUS P35 AFTER CASPASE CLEAVAGE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.1 Å
  • R-Value Free: 0.291 
  • R-Value Work: 0.239 

wwPDB Validation 3D Report Full Report


This is version 1.4 of the entry. See complete history

Literature

Crystal structure of baculovirus P35 reveals a novel conformational change in the reactive site loop after caspase cleavage.

dela Cruz, W.P.Friesen, P.D.Fisher, A.J.

(2001) J.Biol.Chem. 276: 32933-32939

  • DOI: 10.1074/jbc.M103930200
  • Primary Citation of Related Structures:  1I3S

  • PubMed Abstract: 
  • Baculovirus P35 is a universal suppressor of apoptosis that stoichiometrically inhibits cellular caspases in a novel cleavage-dependent mechanism. Upon caspase cleavage at Asp-87, the 10- and 25-kDa cleavage products of P35 remain tightly associated ...

    Baculovirus P35 is a universal suppressor of apoptosis that stoichiometrically inhibits cellular caspases in a novel cleavage-dependent mechanism. Upon caspase cleavage at Asp-87, the 10- and 25-kDa cleavage products of P35 remain tightly associated with the inhibited caspase. Mutations in the alpha-helix of the reactive site loop preceding the cleavage site abrogate caspase inhibition and antiapoptotic activity. Substitution of Pro for Val-71, which is located in the middle of this alpha-helix, produces a protein that is cleaved at the requisite Asp-87 but does not remain bound to the caspase. This loss-of-function mutation provided the opportunity to structurally analyze the conformational changes of the P35 reactive site loop after caspase cleavage. We report here the 2.7 A resolution crystal structure of V71P-mutated P35 after cleavage by human caspase-3. The structure reveals a large movement in the carboxyl-terminal side of the reactive site loop that swings down and forms a new beta-strand that augments an existing beta-sheet. Additionally, the hydrophobic amino terminus releases and extends away from the protein core. Similar movements occur when P35 forms an inhibitory complex with human caspase-8. These findings suggest that the alpha-helix mutation may alter the sequential steps or kinetics of the conformational changes required for inhibition, thereby causing P35 loss of function.


    Related Citations: 
    • Crystal structure of baculovirus P35: role of a novel reactive site loop in apoptotic inhibition
      Fisher, A.J.,dela Cruz, W.P.,Zoog, S.J.,Schneider, C.L.,Friesen, P.D.
      (1999) Embo J. 18: 2031


    Organizational Affiliation

    Department of Chemistry, University of California, Davis, California 95616, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
EARLY 35 KDA PROTEIN
A
298Autographa californica nuclear polyhedrosis virusGene Names: P35
Find proteins for P08160 (Autographa californica nuclear polyhedrosis virus)
Go to UniProtKB:  P08160
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.1 Å
  • R-Value Free: 0.291 
  • R-Value Work: 0.239 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 75.806α = 90.00
b = 75.806β = 90.00
c = 120.693γ = 120.00
Software Package:
Software NamePurpose
CNSrefinement
AMoREphasing
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-10-24
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-10-04
    Type: Refinement description
  • Version 1.4: 2018-01-31
    Type: Experimental preparation