Although E3 ubiquitin-protein ligase DTX4 has not yet been found associated to obstructive nephropathy, using the Kidney & Urinary Pathway Knowledge Base (KUPKB [40],) we observed that it has been found to be induced in models of polycystic kidney disease [41, 42] and in a lupus nephritis model [43]. The gene discussed is DTX4; the disease is polycystic kidney disease.