2VTG

Crystal Structure of Human Iba2, trigonal crystal form


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.204 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural and Functional Characterization of Human Iba Proteins.

Schulze, J.O.Quedenau, C.Roske, Y.Adam, T.Schuler, H.Behlke, J.Turnbull, A.P.Sievert, V.Scheich, C.Mueller, U.Heinemann, U.Bussow, K.

(2008) FEBS J. 275: 4627

  • DOI: 10.1111/j.1742-4658.2008.06605.x
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Iba2 is a homolog of ionized calcium-binding adapter molecule 1 (Iba1), a 17-kDa protein that binds and cross-links filamentous actin (F-actin) and localizes to membrane ruffles and phagocytic cups. Here, we present the crystal structure of human Iba ...

    Iba2 is a homolog of ionized calcium-binding adapter molecule 1 (Iba1), a 17-kDa protein that binds and cross-links filamentous actin (F-actin) and localizes to membrane ruffles and phagocytic cups. Here, we present the crystal structure of human Iba2 and its homodimerization properties, F-actin cross-linking activity, cellular localization and recruitment upon bacterial invasion in comparison with Iba1. The Iba2 structure comprises two central EF-hand motifs lacking bound Ca2+. Iba2 crystallized as a homodimer stabilized by a disulfide bridge and zinc ions. Analytical ultracentrifugation revealed a different mode of dimerization under reducing conditions that was independent of Ca2+. Furthermore, no binding of Ca2+ up to 0.1 mM was detected by equilibrium dialysis. Correspondingly, Iba EF-hand motifs lack residues essential for strong Ca2+ coordination. Sedimentation experiments and microscopy detected pronounced, indistinguishable F-actin binding and cross-linking activity of Iba1 and Iba2 with induction of F-actin bundles. Fluorescent Iba fusion proteins were expressed in HeLa cells and co-localized with F-actin. Iba1 was recruited into cellular projections to a larger extent than Iba2. Additionally, we studied Iba recruitment in a Shigella invasion model that induces cytoskeletal rearrangements. Both proteins were recruited into the bacterial invasion zone and Iba1 was again concentrated slightly higher in the cellular extensions.


    Organizational Affiliation

    Max Delbrück Center for Molecular Medicine, Berlin, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
IONIZED CALCIUM-BINDING ADAPTER MOLECULE 2
A
150Homo sapiensMutation(s): 0 
Gene Names: AIF1L (C9orf58, IBA2)
Find proteins for Q9BQI0 (Homo sapiens)
Go to Gene View: AIF1L
Go to UniProtKB:  Q9BQI0
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
ACT
Query on ACT

Download SDF File 
Download CCD File 
A
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.204 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 70.530α = 90.00
b = 70.530β = 90.00
c = 95.190γ = 120.00
Software Package:
Software NamePurpose
PHASERphasing
XDSdata reduction
REFMACrefinement
SCALAdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-07-14
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Version format compliance