Rabbit anti-Human TAP1 Polyclonal Antibody

Uniprot Id

Q03518

Target Species

Human

Target Name

TAP1

Target Full Name

Antigen peptide transporter 1

Target Function

ABC transporter associated with antigen processing. In complex with TAP2 mediates unidirectional translocation of peptide antigens from cytosol to endoplasmic reticulum (ER) for loading onto MHC class I (MHCI) molecules. Uses the chemical energy of ATP to export peptides against the concentration gradient. During the transport cycle alternates between 'inward-facing' state with peptide binding site facing the cytosol to 'outward-facing' state with peptide binding site facing the ER lumen. Peptide antigen binding to ATP-loaded TAP1-TAP2 induces a switch to hydrolysis-competent 'outward-facing' conformation ready for peptide loading onto nascent MHCI molecules. Subsequently ATP hydrolysis resets the transporter to the 'inward facing' state for a new cycle. Typically transports intracellular peptide antigens of 8 to 13 amino acids that arise from cytosolic proteolysis via IFNG-induced immunoproteasome. Binds peptides with free N- and C-termini, the first three and the C-terminal residues being critical. Preferentially selects peptides having a highly hydrophobic residue at position 3 and hydrophobic or charged residues at the C-terminal anchor. Proline at position 2 has the most destabilizing effect. As a component of the peptide loading complex (PLC), acts as a molecular scaffold essential for peptide-MHCI assembly and antigen presentation.

Target Involvement

Bare lymphocyte syndrome 1 (BLS1)

Target Subcellular Location

Endoplasmic reticulum membrane; Multi-pass membrane protein. Note=The transmembrane segments seem to form a pore in the membrane.

Target Protein Families

ABC transporter superfamily, ABCB family, MHC peptide exporter (TC 3.A.1.209) subfamily

Target Tissue Specificity

Higly expressed in professional APCs monocytes and dendritic cells as well as in lymphocyte subsets T cells, B cells and NK cells.

Target Synonyms

ABC 17; ABC transporter MHC 1; ABC17; ABCB 2; ABCB2; Antigen peptide transporter 1; APT 1; APT1; ATP binding cassette sub family B (MDR/TAP) member 2; ATP binding cassette sub family B member 2; ATP binding cassette transporter; ATP-binding cassette sub-family B member 2; D6S114E; FLJ26666; FLJ41500; Peptide supply factor 1; Peptide transporter involved in antigen processing 1; Peptide transporter PSF 1; Peptide transporter PSF1; Peptide transporter TAP 1; Peptide transporter TAP1; PSF 1; PSF-1; PSF1; Really interesting new gene 4 protein; RING 4; RING4; TAP 1; TAP1; TAP1*0102N; TAP1_HUMAN; TAP1N; Transporter 1 ATP binding cassette sub family B (MDR/TAP); Transporter 1 ATP binding cassette sub family B; Transporter associated with antigen processing; Transporter ATP binding cassette major histocompatibility complex 1; Y3

Target Background

The membrane-associated protein encoded by this gene is a member of the superfamily of ATP-binding cassette (ABC) transporters. ABC proteins transport various molecules across extra- and intra-cellular membranes. ABC genes are divided into seven distinct subfamilies (ABC1, MDR/TAP, MRP, ALD, OABP, GCN20, White). This protein is a member of the MDR/TAP subfamily. Members of the MDR/TAP subfamily are involved in multidrug resistance. The protein encoded by this gene is involved in the pumping of degraded cytosolic peptides across the endoplasmic reticulum into the membrane-bound compartment where class I molecules assemble. Mutations in this gene may be associated with ankylosing spondylitis, insulin-dependent diabetes mellitus, and celiac disease. Two transcript variants encoding different isoforms have been found for this gene.