Enables ubiquitin protein ligase activity. Involved in proteasome-mediated ubiquitin-dependent protein catabolic process and protein K48-linked ubiquitination. Predicted to be located in cytosol; endosome; and membrane. Is expressed in central nervous system; genitourinary system; and retina nuclear layer. Orthologous to human ZNRF1 (zinc and ring finger 1). [provided by Alliance of Genome Resources, Apr 2022]