2XTN

Crystal structure of GTP-bound human GIMAP2, amino acid residues 1- 234


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.185 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural Basis of Oligomerization in Septin-Like Gtpase of Immunity-Associated Protein 2 (Gimap2)

Schwefel, D.Froehlich, C.Eichhorst, J.Wiesner, B.Behlke, J.Aravind, L.Daumke, O.

(2010) Proc.Natl.Acad.Sci.USA 107: 20299

  • DOI: 10.1073/pnas.1010322107
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • GTPases of immunity-associated proteins (GIMAPs) are a distinctive family of GTPases, which control apoptosis in lymphocytes and play a central role in lymphocyte maturation and lymphocyte-associated diseases. To explore their function and mechanism, ...

    GTPases of immunity-associated proteins (GIMAPs) are a distinctive family of GTPases, which control apoptosis in lymphocytes and play a central role in lymphocyte maturation and lymphocyte-associated diseases. To explore their function and mechanism, we determined crystal structures of a representative member, GIMAP2, in different nucleotide-loading and oligomerization states. Nucleotide-free and GDP-bound GIMAP2 were monomeric and revealed a guanine nucleotide-binding domain of the TRAFAC (translation factor associated) class with a unique amphipathic helix α7 packing against switch II. In the absence of α7 and the presence of GTP, GIMAP2 oligomerized via two distinct interfaces in the crystal. GTP-induced stabilization of switch I mediates dimerization across the nucleotide-binding site, which also involves the GIMAP specificity motif and the nucleotide base. Structural rearrangements in switch II appear to induce the release of α7 allowing oligomerization to proceed via a second interface. The unique architecture of the linear oligomer was confirmed by mutagenesis. Furthermore, we showed a function for the GIMAP2 oligomer at the surface of lipid droplets. Although earlier studies indicated that GIMAPs are related to the septins, the current structure also revealed a strikingly similar nucleotide coordination and dimerization mode as in the dynamin GTPase. Based on this, we reexamined the relationships of the septin- and dynamin-like GTPases and demonstrate that these are likely to have emerged from a common membrane-associated dimerizing ancestor. This ancestral property appears to be critical for the role of GIMAPs as nucleotide-regulated scaffolds on intracellular membranes.


    Related Citations: 
    • Purification, Crystallization and Preliminary X- Ray Analysis of Human Gimap2.
      Schwefel, D.,Frohlich, C.,Daumke, O.
      (2010) Acta Crystallogr.,Sect.F 66: 725


    Organizational Affiliation

    Max-Delbrück-Centrum für Molekulare Medizin, Kristallographie, Robert-Rössle-Strasse 10, 13125 Berlin, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
GTPASE IMAP FAMILY MEMBER 2
A
234Homo sapiensMutation(s): 0 
Gene Names: GIMAP2 (IMAP2)
Find proteins for Q9UG22 (Homo sapiens)
Go to Gene View: GIMAP2
Go to UniProtKB:  Q9UG22
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GTP
Query on GTP

Download SDF File 
Download CCD File 
A
GUANOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O14 P3
XKMLYUALXHKNFT-UUOKFMHZSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
GTPKd: 40 nM BINDINGMOAD
GTPKd: 40 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.185 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 58.010α = 90.00
b = 69.200β = 90.00
c = 116.620γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
MOLREPphasing
XDSdata reduction
XDSdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-10-20
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance