title: Major histocompatibility complex-linked transport proteins and antigen processing.
abstract: The major histocompatibility complexes of mice, rats and humans each contain a pair of related genes, Tap-1 and Tap-2, that encode members of a large superfamily of proteins having similar structure and function. The TAP-1 (previously called HAM1 in the mouse) and TAP-2 (HAM2) proteins each contain 6-8 predicted membrane-spanning alpha helices, and a cytoplasmic domain containing a putative ATP-binding site. Recent evidence suggests that a functional TAP-1/TAP-2 heterodimer is required for efficient presentation of antigens to CD8+ cytotoxic T cells. This heterodimer resides in the membrane of the endoplasmic reticulum (ER), and probably functions to transport peptides (produced in the cytoplasm) into the ER lumen for binding to MHC class I molecules.
authors.affiliation: Department of Microbiology and Immunology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-0678.
authors.forename: J J
authors.initials: JJ
authors.lastname: Monaco
mesh_terms: D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D018528:ATP-Binding Cassette Transporters; D000595:Amino Acid Sequence; D000818:Animals; D001693:Biological Transport, Active; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D000949:Histocompatibility Antigens Class II / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000503:physiopathology; D008285:Major Histocompatibility Complex; D008969:Molecular Sequence Data; D016415:Sequence Alignment
chemical_list: D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D018528:ATP-Binding Cassette Transporters; D002352:Carrier Proteins; D000949:Histocompatibility Antigens Class II; C073119:TAP1 protein, human; C486171:Tap1 protein, mouse