Reaction: ATP + H2O + antigen peptide[side 1] = ADP + phosphate + antigen peptide[side 2]
Other name(s): TAP1 (gene name); TAP2 (gene name)
Systematic name: ATP phosphohydrolase (ABC-type, antigen peptide-exporting)
Comments: An ATP-binding cassette (ABC) type transporter, characterized by the presence of two similar ATP-binding domains/proteins and two integral membrane domains/proteins. Does not undergo phosphorylation during the transport process. This entry describes vertebrate transporters involved in the transport of antigens from the cytoplasm to the endoplasmic reticulum for association with major histocompatibility complex (MHC) class I molecules. The substrates are generated mainly from degradation of cytosolic proteins by the proteasome.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Bahram, S., Arnold, D., Bresnahan, M., Strominger, J.L. and Spies, T. Two putative subunits of a peptide pump encoded in the human major histocompatibility complex class II region. Proc. Natl. Acad. Sci. USA 88 (1991) 10094-10098. [PMID: 1946428]
2. Momburg, F., Roelse, J., Howard, J.C., Butcher, G.W., Hammerling, G.J. and Neefjes, J.J. Selectivity of MHC-encoded peptide transporters from human, mouse and rat. Nature 367 (1994) 648-651. [PMID: 8107849]
3. Nijenhuis, M. and Hammerling, G.J. Multiple regions of the transporter associated with antigen processing (TAP) contribute to its peptide binding site. J. Immunol. 157 (1996) 5467-5477. [PMID: 8955196]