Predicted to enable MHC class I protein complex binding activity. Predicted to be involved in negative regulation of antigen processing and presentation of peptide antigen via MHC class I and peptide antigen assembly with MHC class I protein complex. Predicted to act upstream of or within immune system process. Predicted to be located in endoplasmic reticulum. Orthologous to human TAPBPL (TAP binding protein like). [provided by Alliance of Genome Resources, Apr 2022]