(A) Kidneys treated with DAPT and DAPT/IWR1 and stained for LTL, β-laminin, Cdh1, and Podxl–arrowheads indicate LTL-positive nephrons, inserts show magnified nephrons with Podxl staining for podocytes, yellow line outlines nephron tubules. (B) Time-lapse analysis of Wt1+/GFP kidneys treated with DAPT and DAPT + IWR1–arrowheads show GFPHIGH structures in developing proximal segments, red dashed line indicates ureteric bud positions (UB). (C) Structures positive for Jag1 and Wt1 in treated kidneys–arrowheads indicating double-positive structures. (D) qRT-PCR data for Notch target genes (Jag1, Dll1, Heyl, Hey1). All error bars indicate SEM.