title: Presentation of viral antigen by MHC class I molecules is dependent on a putative peptide transporter heterodimer.
abstract: Major histocompatibility complex (MHC) class I molecules present peptides derived from the endogenous protein pool to cytotoxic T lymphocytes, which can thus recognize intracellular antigen. This pathway may depend on a transporter (PSF1) to mediate entry of the cytosolic peptides into a pre-Golgi compartment where they bind to class I heavy chains and promote their stable assembly with beta 2-microglobulin. There is, however, only indirect support for this function of PSF1. Here we show that PSF1 is necessary for the efficient assembly of class I molecules and enables them to present a peptide epitope derived from endogenously synthesized viral antigen. Immunochemical and genetic data demonstrate that the PSF1 polypeptide is associated with a complementary transporter chain, which is polymorphic and is encoded by the PSF2 gene, which is closely linked to PSF1.
authors.affiliation: Division of Tumor Virology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: T
authors.initials: T
authors.lastname: Spies
authors.forename: V
authors.initials: V
authors.lastname: Cerundolo
authors.forename: M
authors.initials: M
authors.lastname: Colonna
authors.forename: P
authors.initials: P
authors.lastname: Cresswell
authors.forename: A
authors.initials: A
authors.lastname: Townsend
authors.forename: R
authors.initials: R
authors.lastname: DeMars
mesh_terms: D000956:Antigens, Viral / Q000276:immunology*; D001483:Base Sequence; D004591:Electrophoresis, Polyacrylamide Gel; D015789:HLA-A2 Antigen / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D006801:Humans; D066298:In Vitro Techniques; D009980:Influenza A virus / Q000276:immunology; D008969:Molecular Sequence Data; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014162:Transfection
chemical_list: D000956:Antigens, Viral; D015789:HLA-A2 Antigen; D015395:Histocompatibility Antigens Class I