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The mechanism of HLA-DM induced peptide exchange in the MHC class II antigen presentation pathway.

ABSTRACT: HLA-DM serves a critical function in the loading and editing of peptides on MHC class II (MHCII) molecules. Recent data showed that the interaction cycle between MHCII molecules and HLA-DM is dependent on the occupancy state of the peptide binding groove. Empty MHCII molecules form stable complexes with HLA-DM, which are disrupted by binding of high-affinity peptide. Interestingly, MHCII molecules with fully engaged peptides cannot interact with HLA-DM, and prior dissociation of the peptide N-terminus from the groove is required for HLA-DM binding. There are significant similarities to the peptide loading process for MHC class I molecules, even though it is executed by a distinct set of proteins in a different cellular compartment.

SUBMITTER: Schulze MS

PROVIDER: S-EPMC3288754 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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The mechanism of HLA-DM induced peptide exchange in the MHC class II antigen presentation pathway.

Schulze Monika-Sarah E D MS Wucherpfennig Kai W KW

Current opinion in immunology 20111202 1

HLA-DM serves a critical function in the loading and editing of peptides on MHC class II (MHCII) molecules. Recent data showed that the interaction cycle between MHCII molecules and HLA-DM is dependent on the occupancy state of the peptide binding groove. Empty MHCII molecules form stable complexes with HLA-DM, which are disrupted by binding of high-affinity peptide. Interestingly, MHCII molecules with fully engaged peptides cannot interact with HLA-DM, and prior dissociation of the peptide N-te ...[more]

PMID: 22138314

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