1. Generation, translocation, and presentation of MHC class I-restricted peptides.
- Author
-
Heemels MT and Ploegh H
- Subjects
- ATP Binding Cassette Transporter, Subfamily B, Member 2, ATP-Binding Cassette Transporters genetics, ATP-Binding Cassette Transporters metabolism, Animals, Antigen Presentation, Biological Transport, Active, Cysteine Endopeptidases metabolism, Histocompatibility Antigens Class I biosynthesis, Histocompatibility Antigens Class I chemistry, Humans, Molecular Chaperones metabolism, Molecular Structure, Multienzyme Complexes metabolism, Peptide Biosynthesis, Proteasome Endopeptidase Complex, Protein Binding, Protein Processing, Post-Translational, Proteins metabolism, T-Lymphocytes immunology, T-Lymphocytes metabolism, Viral Matrix Proteins metabolism, Histocompatibility Antigens Class I metabolism, Peptides immunology, Peptides metabolism
- Abstract
The T lymphocytes of the vertebrate immune system look for changes that take place within the organism by examining a display of peptides at the cell surface. These peptides are presented by the products of the major histocompatibility complex (MHC). MHC class I products present peptides derived by proteolysis of cytosolic proteins by the multicatalytic protease, the proteasome. These peptides are translocated from the cytosol into the endoplasmic reticulum by a dedicated peptide transporter, the transporter associated with antigen presentation (TAP). TAP consists of two subunits, and translocates peptides that are approximately 8-12 residues in length. The COOH terminal residue of the peptide is a major determinant in the specificity of translocation. Following translocation, peptides bind to MHC class I molecules, which depend on the peptide ligand as well as on interactions with chaperonins for proper folding. These complexes then egress from the ER and are transported to their final destination, the cell surface.
- Published
- 1995
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