1YM7

G Protein-Coupled Receptor Kinase 2 (GRK2)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 4.5 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.224 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The role of Gbetagamma and domain interfaces in the activation of G protein-coupled receptor kinase 2

Lodowski, D.T.Barnhill, J.F.Pyskadlo, R.M.Ghirlando, R.Sterne-Marr, R.Tesmer, J.J.G.

(2005) Biochemistry 44: 6958-6970

  • DOI: 10.1021/bi050119q

  • PubMed Abstract: 
  • In response to extracellular signals, G protein-coupled receptors (GPCRs) catalyze guanine nucleotide exchange on Galpha subunits, enabling both activated Galpha and Gbetagamma subunits to target downstream effector enzymes. One target of Gbetagamma ...

    In response to extracellular signals, G protein-coupled receptors (GPCRs) catalyze guanine nucleotide exchange on Galpha subunits, enabling both activated Galpha and Gbetagamma subunits to target downstream effector enzymes. One target of Gbetagamma is G protein-coupled receptor kinase 2 (GRK2), an enzyme that initiates homologous desensitization by phosphorylating activated GPCRs. GRK2 consists of three distinct domains: an RGS homology (RH) domain, a protein kinase domain, and a pleckstrin homology (PH) domain, through which it binds Gbetagamma. The crystal structure of the GRK2-Gbetagamma complex revealed that the domains of GRK2 are intimately associated and left open the possibility for allosteric regulation by Gbetagamma. In this paper, we report the 4.5 A structure of GRK2, which shows that the binding of Gbetagamma does not induce large domain rearrangements in GRK2, although small rotations of the RH and PH domains relative to the kinase domain are evident. Mutation of residues within the larger domain interfaces of GRK2 generally leads to diminished expression and activity, suggesting that these interfaces are important for stability and remain intact upon activation of GRK2. Geranylgeranylated Gbetagamma, but not a soluble mutant of Gbetagamma, protects GRK2 from clostripain digestion at a site within its kinase domain that is 80 A away from the Gbetagamma binding site. Equilibrium ultracentrifugation experiments indicate that neither abnormally large detergent micelles nor protein oligomerization can account for the observed protection. The Gbetagamma-mediated binding of GRK2 to CHAPS micelles or lipid bilayers therefore appears to rigidify the kinase domain, perhaps by encouraging stable contacts between the RH and kinase domains.


    Organizational Affiliation

    Department of Chemistry and Biochemistry, Institute for Cellular and Molecular Biology, The University of Texas at Austin, 78712-0165, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Beta-adrenergic receptor kinase 1
A, B, C, D
689Bos taurusGene Names: ADRBK1 (GRK2)
EC: 2.7.11.15
Find proteins for P21146 (Bos taurus)
Go to UniProtKB:  P21146
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 4.5 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.224 
  • Space Group: P 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 115.162α = 90.00
b = 82.156β = 95.57
c = 218.795γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
SCALEPACKdata scaling
MOLREPphasing
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-07-05
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Advisory, Version format compliance