PDBsum entry 3pl6

Go to PDB code: 
protein ligands Protein-protein interface(s) links
Immune system PDB id
Protein chains
182 a.a. *
181 a.a. *
191 a.a. *
257 a.a. *
NAG ×2
Waters ×93
* Residue conservation analysis
PDB id:
Name: Immune system
Title: Structure of autoimmune tcr hy.1b11 in complex with hla-dq1 85-99
Structure: Mhc class ii hla-dq-alpha chain. Chain: a. Fragment: unp residues 1-194. Engineered: yes. Mhc class ii hla-dq-beta chain. Chain: b. Fragment: unp residues 31-232. Engineered: yes. T-cell receptor alpha chain.
Source: Homo sapiens. Human. Organism_taxid: 9606. Gene: hla-dqa1. Expressed in: cricetulus griseus. Expression_system_taxid: 10029. Expression_system_cell_line: chinese hamster ovary (cho). Gene: hla-dqb1. Expressed in: escherichia coli.
2.55Å     R-factor:   0.232     R-free:   0.258
Authors: D.K.Sethi,K.W.Wucherpfennig
Key ref: D.K.Sethi et al. (2011). A highly tilted binding mode by a self-reactive T cell receptor results in altered engagement of peptide and MHC. J Exp Med, 208, 91. PubMed id: 21199956
13-Nov-10     Release date:   22-Dec-10    
Go to PROCHECK summary

Protein chain
Pfam   ArchSchema ?
Q30066  (Q30066_HUMAN) -  MHC class II HLA-DQ-alpha chain (Fragment)
227 a.a.
182 a.a.
Protein chain
Pfam   ArchSchema ?
Q67AJ6  (Q67AJ6_HUMAN) -  MHC class II antigen (Fragment)
234 a.a.
181 a.a.
Protein chain
No UniProt id for this chain
Struc: 191 a.a.
Protein chain
Key:    PfamA domain  Secondary structure  CATH domain

 Gene Ontology (GO) functional annotation 
  GO annot!
  Cellular component     membrane   2 terms 
  Biological process     immune response   2 terms 
  Biochemical function     structural constituent of myelin sheath     1 term  


J Exp Med 208:91 (2011)
PubMed id: 21199956  
A highly tilted binding mode by a self-reactive T cell receptor results in altered engagement of peptide and MHC.
D.K.Sethi, D.A.Schubert, A.K.Anders, A.Heroux, D.A.Bonsor, C.P.Thomas, E.J.Sundberg, J.Pyrdol, K.W.Wucherpfennig.
Self-reactive T cells that escape elimination in the thymus can cause autoimmune pathology, and it is therefore important to understand the structural mechanisms of self-antigen recognition. We report the crystal structure of a T cell receptor (TCR) from a patient with relapsing-remitting multiple sclerosis that engages its self-peptide-major histocompatibility complex (pMHC) ligand in an unusual manner. The TCR is bound in a highly tilted orientation that prevents interaction of the TCR-α chain with the MHC class II β chain helix. In this structure, only a single germline-encoded TCR loop engages the MHC protein, whereas in most other TCR-pMHC structures all four germline-encoded TCR loops bind to the MHC helices. The tilted binding mode also prevents peptide contacts by the short complementarity-determining region (CDR) 3β loop, and interactions that contribute to peptide side chain specificity are focused on the CDR3α loop. This structure is the first example in which only a single germline-encoded TCR loop contacts the MHC helices. Furthermore, the reduced interaction surface with the peptide may facilitate TCR cross-reactivity. The structural alterations in the trimolecular complex are distinct from previously characterized self-reactive TCRs, indicating that there are multiple unusual ways for self-reactive TCRs to bind their pMHC ligand.