3RDJ

Rat PKC C2 domain Apo


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.245 
  • R-Value Work: 0.225 
  • R-Value Observed: 0.225 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Pb2+ as modulator of protein-membrane interactions.

Morales, K.A.Lasagna, M.Gribenko, A.V.Yoon, Y.Reinhart, G.D.Lee, J.C.Cho, W.Li, P.Igumenova, T.I.

(2011) J Am Chem Soc 133: 10599-10611

  • DOI: https://doi.org/10.1021/ja2032772
  • Primary Citation of Related Structures:  
    3RDJ, 3TWY

  • PubMed Abstract: 

    Lead is a potent environmental toxin that mimics the effects of divalent metal ions, such as zinc and calcium, in the context of specific molecular targets and signaling processes. The molecular mechanism of lead toxicity remains poorly understood. The objective of this work was to characterize the effect of Pb(2+) on the structure and membrane-binding properties of C2α. C2α is a peripheral membrane-binding domain of Protein Kinase Cα (PKCα), which is a well-documented molecular target of lead. Using NMR and isothermal titration calorimetry (ITC) techniques, we established that C2α binds Pb(2+) with higher affinity than its natural cofactor, Ca(2+). To gain insight into the coordination geometry of protein-bound Pb(2+), we determined the crystal structures of apo and Pb(2+)-bound C2α at 1.9 and 1.5 Å resolution, respectively. A comparison of these structures revealed that the metal-binding site is not preorganized and that rotation of the oxygen-donating side chains is required for the metal coordination to occur. Remarkably, we found that holodirected and hemidirected coordination geometries for the two Pb(2+) ions coexist within a single protein molecule. Using protein-to-membrane Förster resonance energy transfer (FRET) spectroscopy, we demonstrated that Pb(2+) displaces Ca(2+) from C2α in the presence of lipid membranes through the high-affinity interaction with the membrane-unbound C2α. In addition, Pb(2+) associates with phosphatidylserine-containing membranes and thereby competes with C2α for the membrane-binding sites. This process can contribute to the inhibitory effect of Pb(2+) on the PKCα activity.


  • Organizational Affiliation

    Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Protein kinase C alpha type137Rattus norvegicusMutation(s): 0 
Gene Names: PrkcaPkca
EC: 2.7.11.13
UniProt
Find proteins for P05696 (Rattus norvegicus)
Explore P05696 
Go to UniProtKB:  P05696
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP05696
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.245 
  • R-Value Work: 0.225 
  • R-Value Observed: 0.225 
  • Space Group: P 32 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 58α = 90
b = 58β = 90
c = 90.46γ = 120
Software Package:
Software NamePurpose
CrystalCleardata collection
MOLREPphasing
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

  • Released Date: 2011-09-07 
  • Deposition Author(s): Li, P.

Revision History  (Full details and data files)

  • Version 1.0: 2011-09-07
    Type: Initial release
  • Version 1.1: 2024-02-21
    Changes: Data collection, Database references