Predicted to enable MHC class II protein complex binding activity. Predicted to be involved in several processes, including antigen processing and presentation of exogenous peptide antigen via MHC class II; negative regulation of antigen processing and presentation of peptide antigen via MHC class II; and peptide antigen assembly with MHC class II protein complex. Predicted to be located in lysosome. Predicted to be part of MHC class II protein complex. Orthologous to human HLA-DOB (major histocompatibility complex, class II, DO beta). [provided by Alliance of Genome Resources, Apr 2022]