1Y1A

CRYSTAL STRUCTURE OF CALCIUM AND INTEGRIN BINDING PROTEIN


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.251 
  • R-Value Work: 0.236 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

The crystal structure of calcium- and integrin-binding protein 1: Insights into redox regulated functions

Blamey, C.J.Ceccarelli, C.Naik, U.P.Bahnson, B.J.

(2005) Protein Sci. 14: 1214-1221

  • DOI: 10.1110/ps.041270805

  • PubMed Abstract: 
  • Calcium- and integrin-binding protein 1 (CIB1) is involved in the process of platelet aggregation by binding the cytoplasmic tail of the alpha(IIb) subunit of the platelet-specific integrin alpha(Iib)beta(3). Although poorly understood, it is widely ...

    Calcium- and integrin-binding protein 1 (CIB1) is involved in the process of platelet aggregation by binding the cytoplasmic tail of the alpha(IIb) subunit of the platelet-specific integrin alpha(Iib)beta(3). Although poorly understood, it is widely believed that CIB1 acts as a global signaling regulator because it is expressed in many tissues that do not express integrin alpha(Iib)beta(3). We report the structure of human CIB1 to a resolution of 2.3 A, crystallized as a dimer. The dimer interface includes an extensive hydrophobic patch in a crystal form with 80% solvent content. Although the dimer form of CIB1 may not be physiologically relevant, this intersub-unit surface is likely to be linked to alpha(IIb) binding and to the binding of other signaling partner proteins. The C-terminal domain of CIB1 is structurally similar to other EF-hand proteins such as calmodulin and calcineurin B. Despite structural homology to the C-terminal domain, the N-terminal domain of CIB1 lacks calcium-binding sites. The structure of CIB1 revealed a complex with a molecule of glutathione in the reduced state bond to the N-terminal domain of one of the two subunits poised to interact with the free thiol of C35. Glutathione bound in this fashion suggests CIB1 may be redox regulated. Next to the bound GSH, the orientation of residues C35, H31, and S48 is suggestive of a cysteine-type protein phosphatase active site. The potential enzymatic activity of CIB1 is discussed and suggests a mechanism by which it regulates a wide variety of proteins in cells in addition to platelets.


    Organizational Affiliation

    Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Calcium and integrin binding 1 (calmyrin)
A, B
183Homo sapiensMutation(s): 0 
Gene Names: CIB1 (CIB, KIP, PRKDCIP)
Find proteins for Q99828 (Homo sapiens)
Go to Gene View: CIB1
Go to UniProtKB:  Q99828
Small Molecules
Ligands 2 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
GSH
Query on GSH

Download SDF File 
Download CCD File 
B
GLUTATHIONE
C10 H17 N3 O6 S
RWSXRVCMGQZWBV-WDSKDSINSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.251 
  • R-Value Work: 0.236 
  • Space Group: P 65 2 2
Unit Cell:
Length (Å)Angle (°)
a = 115.222α = 90.00
b = 115.222β = 90.00
c = 268.202γ = 120.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
CNSrefinement
DENZOdata reduction
SOLVEphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-05-03
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2012-03-07
    Type: Other