The transporter associated with Ag processing (TAP) translocates antigenic peptides into the endoplasmic reticulum for binding onto MHC class I (MHC I) molecules. Tapasin organizes a peptide-loading complex (PLC) by recruiting MHC I and accessory chaperones to the N-terminal regions (N domains) of the TAP subunits TAP1 and TAP2. To investigate the function of the tapasin-docking sites of TAP in...

Sequence analyses of the transporter associated with antigen processing (TAP) in tumor cell lines with deficient MHC class I surface expression identified a bp deletion at position 1489 near the ATP-binding domain of Tap1, causing a frameshift in one melanoma cell line. The impaired TAP1 protein expression was associated with deficient TAP2 protein expression, peptide binding, translocation, an...

A locus encoding polypeptides associated with flagellar structure and function was identified, sequenced, and characterized in Treponema phagedenis and Treponema pallidum. This locus includes homologs of the FlgD, FlgE, MotA, MOB, FliL, and FliM polypeptides found in Salmonella typhimurium and Bacillus subtilis. These polypeptides are extensively conserved between the two treponemes. Several ad...

Antigen presentation to cytotoxic T lymphocytes via major histocompatibility complex class I (MHC I) molecules depends on the heterodimeric transporter associated with antigen processing (TAP). For efficient antigen supply to MHC I molecules in the ER, TAP assembles a macromolecular peptide-loading complex (PLC) by recruiting tapasin. In evolution, TAP appeared together with effector cells of a...

TAP1 and TAP2 genes encode heterodimeric molecule involved in endogenous antigen processing. The present study was undertaken to find out the possible association between TAP1 and TAP2 polymorphisms and risk of pulmonary tuberculosis (PTB) in a sample of Iranian population. Polymorphisms of TAP1 (rs1057141, rs1135216) and TAP2 (rs2228396, rs241447, rs67511411, rs141555015) were determined in 17...

ATP-binding cassette (ABC) transporters form a large family of transmembrane importers and exporters. Using two nucleotide-binding domains (NBDs), which form a canonical ATP-sandwich dimer at some point within the transport cycle, the transporters harness the energy from ATP binding and hydrolysis to drive substrate transport. However the structural elements that enable and tune the dimerizatio...

OBJECTIVES Patients with human papillomavirus (HPV)-positive tonsillar squamous cell carcinoma (TSCC) and base of tongue squamous cell carcinoma (BOTSCC) have a better clinical outcome than those with corresponding HPV-negative tumors. Moreover, there is a strong positive correlation between absent/low as opposed to strong HLA class I expression and favorable clinical outcome for HPV-positive t...

Signal-mediated translocation of proteins occurs across the membranes of several organelles, including the endoplasmic reticulum (ER), peroxisomes, mitochondria and lysosomes. In some cases, signal-mediated translocation involves a well-characterized molecular machine — or translocon — such as the Sec61 complex in the ER. In parallel with these systems, several membranes also have members of th...

The ability of TAP1-/-, beta2m-/-, and TAP1/beta2m-/- mice to mount rejection responses against allogeneic, syngeneic, and MHC class I-deficient tumor grafts was examined. The results demonstrate a potent ability of TAP1-/- and beta2m-/- as well as TAP1/beta2m-/- mice to reject allogeneic tumors. In contrast to published data, rejection of syngeneic MHC class I-expressing tumors was also observ...

Antigen peptides are actively transported across the endoplasmic reticulum by the transporters associated with antigen presentation (TAP). TAP genes polymorphism could influence the selection process that determines which antigen peptides play a role in the pathogenesis of allergic rhinitis. The aim of this study was to investigate the association of TAP genes polymorphism with allergic rhiniti...