Regulator of deubiquitinating complexes. Activates deubiquitinating activity of complexes containing USP12 (PubMed:20147737, PubMed:27373336). Anchors at the base of the ubiquitin-contacting loop of USP12 and remotely modulates the catalytic center of the enzyme (PubMed:27373336). Interacts with USP12 (PubMed:20147737, PubMed:27373336). Component of the USP12/WDR20/WDR48 deubiquitinating complex (PubMed:20147737, PubMed:27373336). Interacts with USP46 (PubMed:20147737).