1NTY

Crystal structure of the first DH/PH domain of Trio to 1.7 A


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.214 
  • R-Value Work: 0.195 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

The C-terminal basic tail of RhoG assists the guanine nucleotide exchange factor trio in binding to phospholipids.

Skowronek, K.R.Guo, F.Zheng, Y.Nassar, N.

(2004) J.Biol.Chem. 279: 37895-37907

  • DOI: 10.1074/jbc.M312677200

  • PubMed Abstract: 
  • The multidomain protein Trio regulates among others neuronal outgrowth and axonal guidance in vertebrates and invertebrates. Trio contains two Dbl-homology/pleckstrin homology (DH/PH) tandem domains that activate several RhoGTPases. Here, we present ...

    The multidomain protein Trio regulates among others neuronal outgrowth and axonal guidance in vertebrates and invertebrates. Trio contains two Dbl-homology/pleckstrin homology (DH/PH) tandem domains that activate several RhoGTPases. Here, we present the x-ray structure of the N-terminal DH/PH, hereafter TrioN, refined to 1.7-A resolution. We show that the relative orientations of the DH and PH domains of TrioN and free Dbs are similar. However, this relative orientation is dissimilar to Dbs in the Dbs/Cdc42 structure. In vitro nucleotide exchange experiments catalyzed by TrioN show that RhoG is approximately 3x more efficiently exchanged than Rac and support the conclusion that RhoG is likely the downstream target of TrioN. Residues 54 and 69, which are not conserved between the two GTPases, are responsible for this specificity. Dot-blot assay reveals that the TrioN-PH domain does not detectably bind phosphatidylinositol 3,4-bisphosphate, PtdIns(3,4)P(2), or other phospholipids. This finding is supported by our three-dimensional structure and affinity binding experiments. Interestingly, the presence of RhoG but not Rac or a C-terminal-truncated RhoG mutant allows TrioN to bind PtdIns(3,4)P(2) with a micromolar affinity constant. We conclude the variable C-terminal basic tail of RhoG specifically assists the recruitment of the TrioN-PH domain to specific membrane-bound phospholipids. Our data suggest a role for the phosphoinositide 3-kinase, PI 3-kinase, in modulating the Trio/RhoG signaling pathway.


    Organizational Affiliation

    Department of Physiology and Biophysics, Stony Brook University, Health Sciences Center, Stony Brook, New York 11794-8661, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Triple functional domain protein
A
311Homo sapiensGene Names: TRIO
EC: 2.7.11.1
Find proteins for O75962 (Homo sapiens)
Go to Gene View: TRIO
Go to UniProtKB:  O75962
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.214 
  • R-Value Work: 0.195 
  • Space Group: P 31 2 1
Unit Cell:
Length (Å)Angle (°)
a = 99.540α = 90.00
b = 99.540β = 90.00
c = 98.294γ = 120.00
Software Package:
Software NamePurpose
CNSrefinement
DENZOdata reduction
ARP/wARPmodel building
AMoREphasing
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-06-29
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2011-11-16
    Type: Atomic model