The DM and DM chain cooperate in the oxidation and folding of HLA-DM1

van Lith, M.; Benham, A.M.

Abstract

HLA-DM (DM) is a heterodimeric MHC molecule that catalyzes the peptide loading of classical MHC class II molecules in the endosomal/lysosomal compartments of APCs. Although the function of DM is well-established, little is known about how DM and -chains fold, oxidize, and form a complex in the endoplasmic reticulum (ER). In this study, we show that glycosylation promotes, but is not essential for, DM ER exit. However, glycosylation of DM N15 is required for oxidation of the -chain. The DM and -chains direct each others fate: single DM chains cannot fully oxidize without DM, while DM forms disulfide-linked homodimers without DM. Correct oxidation and subsequent ER egress depend on the unique DM C25 and C35 residues. This suggests that the C25-C35 disulfide bond in the peptide-binding domain overcomes the need for stabilizing peptides required by other MHC molecules.

Citation

van Lith, M., & Benham, A. (2006). The DM and DM chain cooperate in the oxidation and folding of HLA-DM1. The Journal of Immunology, 177(8), 5430-5439

• Journal Article Type: Article
• Publication Date: Oct 1, 2006
• Deposit Date: May 21, 2007
• Journal: Journal of Immunology
• Print ISSN: 0022-1767
• Electronic ISSN: 1550-6606
• Publisher: American Association of Immunologists
• Peer Reviewed: Peer Reviewed
• Volume: 177
• Issue: 8
• Pages: 5430-5439
• Public URL: https://durham-repository.worktribe.com/output/1554123
• Publisher URL: http://www.jimmunol.org/cgi/content/abstract/177/8/5430