An ATP-binding cassette, sub-family B protein (ATP BINDING CASSETTE TRANSPORTER, SUBFAMILY B) that functions in the transport of ANTIGENS from the CYTOPLASM to the ENDOPLASMIC RETICULUM for association with HISTOCOMPATIBILITY ANTIGENS CLASS I peptides. It also acts as a molecular scaffold for the final stage of MHC class I PROTEIN FOLDING.

Synonyms: TAP1, Peptide Transporter, RING4 Protein, ATP Binding Cassette Sub Family B Member 2, TAP1 Protein, TAP-1 Protein, ATP Binding Cassette Transporter, Subfamily B, Member 2, Antigen Peptide Transporter 1, Really Interesting New Gene 4 Protein, 0, Antigen Peptide Transporter-1, PSF1, Peptide Transporter, Peptide Transporter TAP1, Peptide Transporter PSF1, TAP 1 Protein, ATP-Binding Cassette Sub-Family B Member 2, ATP Binding Cassette Transporter, Sub-Family B, Member 2, ABCB2 Protein, Transporter 1, ATP-Binding Cassette, Sub-Family B (MDR-TAP)