Predicted to enable several functions, including MHC class II receptor activity; peptide antigen binding activity; and signaling receptor binding activity. Involved in response to interferon-gamma. Acts upstream of or within antigen processing and presentation of exogenous peptide antigen via MHC class II. Predicted to be located in external side of plasma membrane and immunological synapse. Predicted to be part of MHC class II protein complex. Predicted to be active in late endosome membrane and lysosomal membrane. Is expressed in lung. Human ortholog(s) of this gene implicated in several diseases, including asthma (multiple); autoimmune disease (multiple); bacterial infectious disease (multiple); eye disease (multiple); and sarcoidosis (multiple). Orthologous to human HLA-DRB1 (major histocompatibility complex, class II, DR beta 1) and HLA-DRB5 (major histocompatibility complex, class II, DR beta 5).