Molecular machinations of the MHC-I peptide loading complex.
The acquisition of an optimal peptide ligand by MHC class I molecules is crucial for the generation of immunity to viruses and tumors. This process is orchestrated by a molecular machine known as the peptide loading complex (PLC) that consists of specialized and general ER-resident molecules. These proteins collaborate to ensure the loading of an optimal peptide ligand into the antigen binding cleft of class I molecules. The surprising diversity of peptides bound to MHC class I molecules and recapitulation of class I assembly in vitro have provided new insights into the molecular machinations of peptide loading. Coupled with the extraordinary polymorphism of class I molecules and their differential dependence on various components of the PLC for cell surface expression, a picture of peptide loading at the molecular level has recently emerged and will be discussed herein.
Purcell
Anthony W
AW
Department of Biochemistry and Molecular Biology, Bio21 Institute for Molecular Science and Biotechnology, University of Melbourne, Parkville, Victoria 3010, Australia.
Elliott
Tim
T
D017951:Antigen Presentation; D004721:Endoplasmic Reticulum / Q000378:metabolism; D015395:Histocompatibility Antigens Class I / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D010455:Peptides / Q000737:chemistry / Q000276:immunology*; D011110:Polymorphism, Genetic
D015395:Histocompatibility Antigens Class I; D010455:Peptides