Plasminogen activator inhibitor 1 (PAI-1) regulates fibrinolysis and the plasmin-mediated ECM matrix metalloproteinase activation.18,19 PAI-1 contributes to renal fibrosis by promoting migration of profibrotic cells through a protease-independent mechanism.19 In this study, immunohistochemical staining and western blot analyses revealed upregulation of PAI-1 in obstructed kidneys of Atg7flox/flox;Ksp-Cre+ mice after UUO (Supplementary Fig. 1c and d). The gene discussed is SERPINE1; the disease is renal fibrosis.