title: Processing of major histocompatibility class I-restricted antigens in the endoplasmic reticulum.
abstract: We have introduced long precursor peptides directly into the endoplasmic reticulum (ER) of a mutant cell line (T2-Db) that lacks the ability to transport peptides from the cytosol to the ER in a transporter associated with antigen processing (TAP) dependent way. This was done by expressing various influenza A-derived peptides containing the naturally processed epitope ASNENMDAM (366-374) preceded by the influenza hemagglutinin ER translocation sequence. Peptides derived from these minigenes that became associated with Db were isolated and identified by combined reversed phase liquid chromatography and detection by cytotoxic T lymphocytes. Our results establish that NH2-terminal extensions of at least 40 residues can be trimmed from peptides entering the ER, but that proteolysis of larger proteins may be limited.
authors.affiliation: Institute for Molecular Medicine, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: T
authors.initials: T
authors.lastname: Elliott
authors.forename: A
authors.initials: A
authors.lastname: Willis
authors.forename: V
authors.initials: V
authors.lastname: Cerundolo
authors.forename: A
authors.initials: A
authors.lastname: Townsend
mesh_terms: D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters / Q000502:physiology*; D000595:Amino Acid Sequence; D000818:Animals; D017951:Antigen Presentation; D001692:Biological Transport; D020126:Brefeldin A; D002451:Cell Compartmentation; D002738:Chloroquine / Q000494:pharmacology; D003517:Cyclopentanes / Q000494:pharmacology; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D006183:H-2 Antigens / Q000276:immunology*; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006389:Hemagglutinins, Viral / Q000276:immunology / Q000378:metabolism*; D016056:Immunodominant Epitopes / Q000276:immunology / Q000378:metabolism*; D007739:L Cells; D051379:Mice; D008808:Mice, Inbred CBA; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology / Q000378:metabolism*; D014107:Tosyllysine Chloromethyl Ketone / Q000494:pharmacology
chemical_list: D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters; D003517:Cyclopentanes; D006183:H-2 Antigens; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006389:Hemagglutinins, Viral; D016056:Immunodominant Epitopes; D010446:Peptide Fragments; C073119:TAP1 protein, human; C486171:Tap1 protein, mouse; C489516:Tap2 protein, mouse; C071692:TAP2 protein, human; D020126:Brefeldin A; D014107:Tosyllysine Chloromethyl Ketone; D002738:Chloroquine