PKD1 and nephronophthisis: These findings indicate that the association of Glis2 inactivation with epithelial cell senescence in the kidney is a feature of germline null nephronophthisis phenotypes and not a feature of postnatal kidney tubule selective inactivation of Glis2. Overall, adult inducible tubule specific inactivation of Glis2 in kidney epithelial cells suppresses kidney cyst growth following Pkd1 inactivation without evidence of untoward effects on kidney structure or function.