1I4O

CRYSTAL STRUCTURE OF THE XIAP/CASPASE-7 COMPLEX


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.224 

wwPDB Validation   3D Report Full Report


This is version 1.5 of the entry. See complete history


Literature

Structural basis of caspase inhibition by XIAP: differential roles of the linker versus the BIR domain.

Huang, Y.Park, Y.C.Rich, R.L.Segal, D.Myszka, D.G.Wu, H.

(2001) Cell 104: 781-790

  • Primary Citation of Related Structures:  
    1I4O

  • PubMed Abstract: 
  • The inhibitor of apoptosis proteins (IAPs) represent the only endogenous caspase inhibitors and are characterized by the presence of baculoviral IAP repeats (BIRs). Here, we report the crystal structure of the complex between human caspase-7 and XIAP (BIR2 and the proceeding linker) ...

    The inhibitor of apoptosis proteins (IAPs) represent the only endogenous caspase inhibitors and are characterized by the presence of baculoviral IAP repeats (BIRs). Here, we report the crystal structure of the complex between human caspase-7 and XIAP (BIR2 and the proceeding linker). The structure surprisingly reveals that the linker is the only contacting element for the caspase, while the BIR2 domain is invisible in the crystal. The linker interacts with and blocks the substrate groove of the caspase in a backward fashion, distinct from substrate recognition. Structural analyses suggest that the linker is the energetic and specificity determinant of the interaction. Further biochemical characterizations clearly establish that the linker harbors the major energetic determinant, while the BIR2 domain serves as a regulatory element for caspase binding and Smac neutralization.


    Organizational Affiliation

    Program in Physiology, Biophysics and Molecular Medicine, Graduate School of Medical Sciences, of Cornell University, 1300 York Avenue, New York, NY 10021, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
CASPASE-7 AB280Homo sapiensMutation(s): 0 
Gene Names: CASP7MCH3
EC: 3.4.22 (PDB Primary Data), 3.4.22.60 (UniProt)
Find proteins for P55210 (Homo sapiens)
Explore P55210 
Go to UniProtKB:  P55210
NIH Common Fund Data Resources
PHAROS:  P55210
Protein Feature View
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
BACULOVIRAL IAP REPEAT-CONTAINING PROTEIN 4 CD141Homo sapiensMutation(s): 0 
Gene Names: XIAPAPI3BIRC4IAP3
EC: 2.3.2.27
Find proteins for P98170 (Homo sapiens)
Explore P98170 
Go to UniProtKB:  P98170
NIH Common Fund Data Resources
PHAROS:  P98170
Protein Feature View
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.224 
  • Space Group: P 32 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 88.5α = 90
b = 88.5β = 90
c = 185.4γ = 120
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2001-03-21
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2011-11-16
    Changes: Atomic model
  • Version 1.4: 2013-09-25
    Changes: Derived calculations
  • Version 1.5: 2017-10-04
    Changes: Refinement description