The function of ENSG00000231925 (TAPBP, TAP binding protein) is as follows. Involved in the association of MHC class I with transporter associated with antigen processing (TAP) and in the assembly of MHC class I with peptide (peptide loading). {ECO:0000269|PubMed:10636848, ECO:0000269|PubMed:12582157, ECO:0000269|PubMed:21263072, ECO:0000269|PubMed:26611325}.