6] Thiol oxidation and reduction in major histocompatibility complex class I-restricted antigen processing and presentation

Abstract

Publisher Summary This chapter presents a general method for the identification of glycoproteins interacting with ERp57 and its application to the study of the major histocompatibility complex (MHC) class I loading complex. MHC class I molecules deliver endogenous peptides to the cell surface for inspection by the immune system. Assembly of class I peptide complexes takes place in the oxidizing environment of the endoplasmic reticulum (ER) and involves the formation of disulfide bonds in the MHC class I molecule. The class I assembly machinery includes the thiol-dependent oxidoreductase ERp57. This molecule is a member of the protein disulfide isomerase (PDI) family and contains two distinct thioredoxin (TR) motifs. ERp57 is known to be specifically recruited to nascent glycoproteins by either calreticulin (CRT) or calnexin (CNX). Its capability to mediate disulfide bond rearrangements in glycoproteins has been demonstrated in vitro and in vivo and is outlined in the chapter.