1ogt
CRYSTAL STRUCTURE OF HLA-B*2705 COMPLEXED WITH THE VASOACTIVE INTESTINAL PEPTIDE TYPE 1 RECEPTOR (VIPR) PEPTIDE (RESIDUES 400-408)
OverviewOverview
The products of the human leukocyte antigen subtypes HLA-B*2705 and HLA-B*2709 differ only in residue 116 (Asp vs. His) within the peptide binding groove but are differentially associated with the autoimmune disease ankylosing spondylitis (AS); HLA-B*2705 occurs in AS-patients, whereas HLA-B*2709 does not. The subtypes also generate differential T cell repertoires as exemplified by distinct T cell responses against the self-peptide pVIPR (RRKWRRWHL). The crystal structures described here show that pVIPR binds in an unprecedented dual conformation only to HLA-B*2705 molecules. In one binding mode, peptide pArg5 forms a salt bridge to Asp116, connected with drastically different interactions between peptide and heavy chain, contrasting with the second, conventional conformation, which is exclusively found in the case of B*2709. These subtype-dependent differences in pVIPR binding link the emergence of dissimilar T cell repertoires in individuals with HLA-B*2705 or HLA-B*2709 to the buried Asp116/His116 polymorphism and provide novel insights into peptide presentation by major histocompatibility antigens.
About this StructureAbout this Structure
1OGT is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
ReferenceReference
Dual, HLA-B27 subtype-dependent conformation of a self-peptide., Hulsmeyer M, Fiorillo MT, Bettosini F, Sorrentino R, Saenger W, Ziegler A, Uchanska-Ziegler B, J Exp Med. 2004 Jan 19;199(2):271-81. PMID:14734527 Page seeded by OCA on Sat May 3 03:49:38 2008