Enables aminopeptidase activity; tumor necrosis factor receptor binding activity; and zinc ion binding activity. Involved in proteolysis. Located in endoplasmic reticulum lumen. Human ortholog(s) of this gene implicated in cervix carcinoma. Orthologous to human ERAP1 (endoplasmic reticulum aminopeptidase 1). [provided by Alliance of Genome Resources, Apr 2022]