5ib3

Publication Abstract from PubMed

Conformational changes of major histocompatibility complex (MHC) antigens have the potential to be recognized by T cells and may arise from polymorphic variation of the MHC molecule, the binding of modifying ligands, or both. Here, we investigated whether metal ions could affect allele-dependent structural variation of the two minimally distinct human leukocyte antigen (HLA)-B*27:05 and HLA-B*27:09 subtypes, which exhibit differential association with the rheumatic disease ankylosing spondylitis (AS). We employed NMR spectroscopy and X-ray crystallography coupled with ensemble refinement to study the AS-associated HLA-B*27:05 subtype and the AS non-associated HLA-B* 27:09 in complex with the self-peptide pVIPR (RRKWRRWHL). Both techniques revealed that pVIPR exhibits a higher degree of flexibility when complexed with HLA-B* 27:05 than with HLA-B*27:09. Furthermore, we found that the binding of the metal ions Cu2+ or Ni2+, but not Mn2+, Zn2+, or Hg2+ affects the structure of a pVIPR-bound HLA-B*27 molecule in a subtype-dependent manner. In HLA-B*27:05, the metals triggered conformational reorientations of pVIPR, but no such structural changes were observed in the HLA-B*27:09 subtype, with or without bound metal ion. These observations provide the first demonstration that not only MHC class II, but also class I molecules can undergo metal ion-induced conformational alterations. Our findings suggest that metals may have role in triggering rheumatic diseases such as AS and also have implications for the molecular basis of metal-induced hypersensitivities and allergies.

Metal-triggered conformational reorientation of a self-peptide bound to a disease-associated HLA-B*27 subtype.,Driller R, Ballaschk M, Schmieder P, Uchanska-Ziegler B, Ziegler A, Loll B J Biol Chem. 2019 Jul 11. pii: RA119.008937. doi: 10.1074/jbc.RA119.008937. PMID:31296658^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.