4ZD3

Structure of a transglutaminase 2-specific autoantibody Fab fragment


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.200 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural Basis for Antigen Recognition by Transglutaminase 2-specific Autoantibodies in Celiac Disease.

Chen, X.Hnida, K.Graewert, M.A.Andersen, J.T.Iversen, R.Tuukkanen, A.Svergun, D.Sollid, L.M.

(2015) J.Biol.Chem. 290: 21365-21375

  • DOI: 10.1074/jbc.M115.669895

  • PubMed Abstract: 
  • Antibodies to the autoantigen transglutaminase 2 (TG2) are a hallmark of celiac disease. We have studied the interaction between TG2 and an anti-TG2 antibody (679-14-E06) derived from a single gut IgA plasma cell of a celiac disease patient. The anti ...

    Antibodies to the autoantigen transglutaminase 2 (TG2) are a hallmark of celiac disease. We have studied the interaction between TG2 and an anti-TG2 antibody (679-14-E06) derived from a single gut IgA plasma cell of a celiac disease patient. The antibody recognizes one of four identified epitopes targeted by antibodies of plasma cells of the disease lesion. The binding interface was identified by small angle x-ray scattering, ab initio and rigid body modeling using the known crystal structure of TG2 and the crystal structure of the antibody Fab fragment, which was solved at 2.4 Å resolution. The result was confirmed by testing binding of the antibody to TG2 mutants by ELISA and surface plasmon resonance. TG2 residues Arg-116 and His-134 were identified to be critical for binding of 679-14-E06 as well as other epitope 1 antibodies. In contrast, antibodies directed toward the two other main epitopes (epitopes 2 and 3) were not affected by these mutations. Molecular dynamics simulations suggest interactions of 679-14-E06 with the N-terminal domain of TG2 via the CDR2 and CDR3 loops of the heavy chain and the CDR2 loop of the light chain. In addition there were contacts of the framework 3 region of the heavy chain with the catalytic domain of TG2. The results provide an explanation for the biased usage of certain heavy and light chain gene segments by epitope 1-specific antibodies in celiac disease.


    Organizational Affiliation

    From the Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, N-0372 Oslo, Norway and.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
679-14-14E06 Fab fragment heavy chain
H
224N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
679-14-14E06 Fab fragment light chain
L
216N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.200 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 50.340α = 90.00
b = 61.380β = 100.90
c = 79.050γ = 90.00
Software Package:
Software NamePurpose
Aimlessdata scaling
PHENIXrefinement
PHASERphasing
MOSFLMdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
South-Eastern Norway Regional Health AuthorityNorway--
Research Council of NorwayNorway179573/V40
European Community's Seventh Framework ProgrammeNorwayMRTN-CT-2011-289964
European Community's Seventh Framework ProgrammeNorwayERC-2010-Ad-268541

Revision History 

  • Version 1.0: 2015-07-22
    Type: Initial release
  • Version 1.1: 2015-09-09
    Type: Database references