2V4Z

The crystal structure of the human G-protein subunit alpha (GNAI3) in complex with an engineered regulator of G-protein signaling type 2 domain (RGS2)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.208 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural Determinants of G-Protein Alpha Subunit Selectivity by Regulator of G-Protein Signaling 2(Rgs2).

Kimple, A.J.Soundararajan, M.Hutsell, S.Q.Roos, A.K.Urban, D.J.Setola, V.Temple, B.R.Roth, B.L.Knapp, S.Willard, F.S.Siderovski, D.P.

(2009) J.Biol.Chem. 284: 19402

  • DOI: 10.1074/jbc.M109.024711

  • PubMed Abstract: 
  • "Regulator of G-protein signaling" (RGS) proteins facilitate the termination of G protein-coupled receptor (GPCR) signaling via their ability to increase the intrinsic GTP hydrolysis rate of Galpha subunits (known as GTPase-accelerating protein or "G ...

    "Regulator of G-protein signaling" (RGS) proteins facilitate the termination of G protein-coupled receptor (GPCR) signaling via their ability to increase the intrinsic GTP hydrolysis rate of Galpha subunits (known as GTPase-accelerating protein or "GAP" activity). RGS2 is unique in its in vitro potency and selectivity as a GAP for Galpha(q) subunits. As many vasoconstrictive hormones signal via G(q) heterotrimer-coupled receptors, it is perhaps not surprising that RGS2-deficient mice exhibit constitutive hypertension. However, to date the particular structural features within RGS2 determining its selectivity for Galpha(q) over Galpha(i/o) substrates have not been completely characterized. Here, we examine a trio of point mutations to RGS2 that elicits Galpha(i)-directed binding and GAP activities without perturbing its association with Galpha(q). Using x-ray crystallography, we determined a model of the triple mutant RGS2 in complex with a transition state mimetic form of Galpha(i) at 2.8-A resolution. Structural comparison with unliganded, wild type RGS2 and of other RGS domain/Galpha complexes highlighted the roles of these residues in wild type RGS2 that weaken Galpha(i) subunit association. Moreover, these three amino acids are seen to be evolutionarily conserved among organisms with modern cardiovascular systems, suggesting that RGS2 arose from the R4-subfamily of RGS proteins to have specialized activity as a potent and selective Galpha(q) GAP that modulates cardiovascular function.


    Organizational Affiliation

    Departments of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
GUANINE NUCLEOTIDE-BINDING PROTEIN G(K) SUBUNIT ALPHA
A
350Homo sapiensMutation(s): 0 
Gene Names: GNAI3
Find proteins for P08754 (Homo sapiens)
Go to Gene View: GNAI3
Go to UniProtKB:  P08754
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
REGULATOR OF G-PROTEIN SIGNALING 2
B
142Homo sapiensMutation(s): 3 
Gene Names: RGS2 (G0S8)
Find proteins for P41220 (Homo sapiens)
Go to Gene View: RGS2
Go to UniProtKB:  P41220
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GDP
Query on GDP

Download SDF File 
Download CCD File 
A
GUANOSINE-5'-DIPHOSPHATE
C10 H15 N5 O11 P2
QGWNDRXFNXRZMB-UUOKFMHZSA-N
 Ligand Interaction
ALF
Query on ALF

Download SDF File 
Download CCD File 
A
TETRAFLUOROALUMINATE ION
Al F4
UYOMQIYKOOHAMK-UHFFFAOYSA-J
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.208 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 114.539α = 90.00
b = 114.539β = 90.00
c = 99.330γ = 120.00
Software Package:
Software NamePurpose
REFMACrefinement
PHASERphasing
SCALAdata scaling
MOSFLMdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-11-04
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Version format compliance
  • Version 1.2: 2018-04-04
    Type: Data collection