1I4O

CRYSTAL STRUCTURE OF THE XIAP/CASPASE-7 COMPLEX


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 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


  • 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 ...

    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: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CASPASE-7
A, B
280Homo sapiensMutation(s): 0 
Gene Names: CASP7 (MCH3)
EC: 3.4.22.60
Find proteins for P55210 (Homo sapiens)
Go to Gene View: CASP7
Go to UniProtKB:  P55210
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
BACULOVIRAL IAP REPEAT-CONTAINING PROTEIN 4
C, D
141Homo sapiensMutation(s): 0 
Gene Names: XIAP (API3, BIRC4, IAP3)
EC: 2.3.2.27
Find proteins for P98170 (Homo sapiens)
Go to Gene View: XIAP
Go to UniProtKB:  P98170
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.224 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 88.500α = 90.00
b = 88.500β = 90.00
c = 185.400γ = 120.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-03-21
    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: 2011-11-16
    Type: Atomic model
  • Version 1.4: 2013-09-25
    Type: Derived calculations
  • Version 1.5: 2017-10-04
    Type: Refinement description