3C7K

Molecular architecture of Galphao and the structural basis for RGS16-mediated deactivation


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.311 
  • R-Value Work: 0.250 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Molecular architecture of G{alpha}o and the structural basis for RGS16-mediated deactivation.

Slep, K.C.Kercher, M.A.Wieland, T.Chen, C.K.Simon, M.I.Sigler, P.B.

(2008) Proc.Natl.Acad.Sci.Usa 105: 6243-6248

  • DOI: 10.1073/pnas.0801569105
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Heterotrimeric G proteins relay extracellular cues from heptahelical transmembrane receptors to downstream effector molecules. Composed of an alpha subunit with intrinsic GTPase activity and a betagamma heterodimer, the trimeric complex dissociates u ...

    Heterotrimeric G proteins relay extracellular cues from heptahelical transmembrane receptors to downstream effector molecules. Composed of an alpha subunit with intrinsic GTPase activity and a betagamma heterodimer, the trimeric complex dissociates upon receptor-mediated nucleotide exchange on the alpha subunit, enabling each component to engage downstream effector targets for either activation or inhibition as dictated in a particular pathway. To mitigate excessive effector engagement and concomitant signal transmission, the Galpha subunit's intrinsic activation timer (the rate of GTP hydrolysis) is regulated spatially and temporally by a class of GTPase accelerating proteins (GAPs) known as the regulator of G protein signaling (RGS) family. The array of G protein-coupled receptors, Galpha subunits, RGS proteins and downstream effectors in mammalian systems is vast. Understanding the molecular determinants of specificity is critical for a comprehensive mapping of the G protein system. Here, we present the 2.9 A crystal structure of the enigmatic, neuronal G protein Galpha(o) in the GTP hydrolytic transition state, complexed with RGS16. Comparison with the 1.89 A structure of apo-RGS16, also presented here, reveals plasticity upon Galpha(o) binding, the determinants for GAP activity, and the structurally unique features of Galpha(o) that likely distinguish it physiologically from other members of the larger Galpha(i) family, affording insight to receptor, GAP and effector specificity.


    Organizational Affiliation

    Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA. kslep@bio.unc.edu




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Guanine nucleotide-binding protein G(o) subunit alpha
A, C
333Mus musculusMutation(s): 0 
Gene Names: Gnao1 (Gna0, Gnao)
Find proteins for P18872 (Mus musculus)
Go to UniProtKB:  P18872
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Regulator of G-protein signaling 16
B, D
129Mus musculusMutation(s): 0 
Gene Names: Rgs16 (Rgsr)
Find proteins for P97428 (Mus musculus)
Go to UniProtKB:  P97428
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GDP
Query on GDP

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

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

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

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.311 
  • R-Value Work: 0.250 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 96.357α = 90.00
b = 96.357β = 90.00
c = 235.610γ = 120.00
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
CNSrefinement
PDB_EXTRACTdata extraction
CNSphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-05-06
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2017-10-25
    Type: Refinement description