1KXR

Crystal Structure of Calcium-Bound Protease Core of Calpain I


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.07 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.213 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

A Ca(2+) switch aligns the active site of calpain.

Moldoveanu, T.Hosfield, C.M.Lim, D.Elce, J.S.Jia, Z.Davies, P.L.

(2002) Cell 108: 649-660

  • Also Cited By: 1TL9, 3DF0

  • PubMed Abstract: 
  • Ca(2+) signaling by calpains leads to controlled proteolysis during processes ranging from cytoskeleton remodeling in mammals to sex determination in nematodes. Deregulated Ca(2+) levels result in aberrant proteolysis by calpains, which contributes t ...

    Ca(2+) signaling by calpains leads to controlled proteolysis during processes ranging from cytoskeleton remodeling in mammals to sex determination in nematodes. Deregulated Ca(2+) levels result in aberrant proteolysis by calpains, which contributes to tissue damage in heart and brain ischemias as well as neurodegeneration in Alzheimer's disease. Here we show that activation of the protease core of mu calpain requires cooperative binding of two Ca(2+) atoms at two non-EF-hand sites revealed in the 2.1 A crystal structure. Conservation of the Ca(2+) binding residues defines an ancestral general mechanism of activation for most calpain isoforms, including some that lack EF-hand domains. The protease region is not affected by the endogenous inhibitor, calpastatin, and may contribute to calpain-mediated pathologies when the core is released by autoproteolysis.


    Organizational Affiliation

    Department of Biochemistry and the Protein, Engineering Network of Centres of Excellence, Queen's University, Kingston, Ontario, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
thiol protease DOMAINS I AND II
A, B
339Rattus norvegicusGene Names: Capn1 (Cls1)
EC: 3.4.22.52
Find proteins for P97571 (Rattus norvegicus)
Go to UniProtKB:  P97571
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download SDF File 
Download CCD File 
A, B
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.07 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.213 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 149.443α = 90.00
b = 40.492β = 105.96
c = 132.328γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
CNSrefinement
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-03-20
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance