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Dipeptides catalyze rapid peptide exchange on MHC class I molecules.

ABSTRACT: Peptide ligand selection by MHC class I molecules, which occurs by iterative optimization, is the centerpiece of immunodominance in antiviral and antitumor immune responses. For its understanding, the molecular mechanisms of peptide binding and dissociation by class I molecules must be elucidated. To this end, we have investigated dipeptides that bind to the F pocket of class I molecules. We find that they accelerate the dissociation of prebound peptides of both low and high affinity, suggesting a mechanism of action for the peptide-exchange chaperone tapasin. Peptide exchange on class I molecules also has practical uses in epitope discovery and T-cell monitoring.

SUBMITTER: Saini SK

PROVIDER: S-EPMC4291614 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Dipeptides catalyze rapid peptide exchange on MHC class I molecules.

Saini Sunil Kumar SK Schuster Heiko H Ramnarayan Venkat Raman VR Rammensee Hans-Georg HG Stevanović Stefan S Springer Sebastian S

Proceedings of the National Academy of Sciences of the United States of America 20141222 1

Peptide ligand selection by MHC class I molecules, which occurs by iterative optimization, is the centerpiece of immunodominance in antiviral and antitumor immune responses. For its understanding, the molecular mechanisms of peptide binding and dissociation by class I molecules must be elucidated. To this end, we have investigated dipeptides that bind to the F pocket of class I molecules. We find that they accelerate the dissociation of prebound peptides of both low and high affinity, suggesting ...[more]

PMID: 25535340

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