6BIJ

HLA-DRB1 in complex with citrullinated fibrinogen peptide


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.239 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.184 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

The interplay between citrullination and HLA-DRB1 polymorphism in shaping peptide binding hierarchies in rheumatoid arthritis.

Ting, Y.T.Petersen, J.Ramarathinam, S.H.Scally, S.W.Loh, K.L.Thomas, R.Suri, A.Baker, D.G.Purcell, A.W.Reid, H.H.Rossjohn, J.

(2018) J Biol Chem 293: 3236-3251

  • DOI: 10.1074/jbc.RA117.001013
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • The HLA-DRB1 locus is strongly associated with rheumatoid arthritis (RA) susceptibility, whereupon citrullinated self-peptides bind to HLA-DR molecules bearing the shared epitope (SE) amino acid motif. However, the differing propensity for c ...

    The HLA-DRB1 locus is strongly associated with rheumatoid arthritis (RA) susceptibility, whereupon citrullinated self-peptides bind to HLA-DR molecules bearing the shared epitope (SE) amino acid motif. However, the differing propensity for citrullinated/non-citrullinated self-peptides to bind given HLA-DR allomorphs remains unclear. Here, we used a fluorescence polarization assay to determine a hierarchy of binding affinities of 34 self-peptides implicated in RA against three HLA-DRB1 allomorphs (HLA-DRB1*04:01/*04:04/*04:05) each possessing the SE motif. For all three HLA-DRB1 allomorphs, we observed a strong correlation between binding affinity and citrullination at P4 of the bound peptide ligand. A differing hierarchy of peptide-binding affinities across the three HLA-DRB1 allomorphs was attributable to the β-chain polymorphisms that resided outside the SE motif and were consistent with sequences of naturally presented peptide ligands. Structural determination of eight HLA-DR4-self-epitope complexes revealed strict conformational convergence of the P4-Cit and surrounding HLA β-chain residues. Polymorphic residues that form part of the P1 and P9 pockets of the HLA-DR molecules provided a structural basis for the preferential binding of the citrullinated self-peptides to the HLA-DR4 allomorphs. Collectively, we provide a molecular basis for the interplay between citrullination of self-antigens and HLA polymorphisms that shape peptide-HLA-DR4 binding affinities in RA.


    Organizational Affiliation

    the Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, Wales, United Kingdom.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
HLA class II histocompatibility antigen, DRB1-4 beta chain
B
189Homo sapiensMutation(s): 0 
Gene Names: HLA-DRB1
Find proteins for P01911 (Homo sapiens)
Go to UniProtKB:  P01911
NIH Common Fund Data Resources
PHAROS  P01911
Protein Feature View
  • Reference Sequence
  • Find similar proteins by: Sequence   |   Structure
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Citrullinated Fibrinogen 72,74Cit69-81
C
13Homo sapiensMutation(s): 0 
Gene Names: FGB
Find proteins for P02675 (Homo sapiens)
Go to UniProtKB:  P02675
NIH Common Fund Data Resources
PHAROS  P02675
Protein Feature View
  • Reference Sequence

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
HLA class II histocompatibility antigen, DR alpha chain
A
177Homo sapiensMutation(s): 0 
Gene Names: HLA-DRAHLA-DRA1
Find proteins for P01903 (Homo sapiens)
Go to UniProtKB:  P01903
NIH Common Fund Data Resources
PHAROS  P01903
Protein Feature View
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAG
Query on NAG

Download CCD File 
A
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
CIR
Query on CIR
CL-PEPTIDE LINKINGC6 H13 N3 O3ARG
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.239 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.184 
  • Space Group: C 2 2 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 67.01α = 90
b = 177.71β = 90
c = 77.04γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
Aimlessdata scaling
PDB_EXTRACTdata extraction
XDSdata reduction
PHASERphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2018-01-17
    Type: Initial release
  • Version 1.1: 2018-01-24
    Changes: Database references, Structure summary
  • Version 1.2: 2018-03-14
    Changes: Advisory, Database references