Fig. 1. Loss of Notch2 causes hypoplastic kidneys that do not develop glomeruli, proximal tubules or S-shaped bodies. (A-D) The urinary system from postnatal day 1 and day 2 wild-type (A,B) or mutant (C,D) animals. Note the size difference of the urinary bladder (arrow in A and C). The mutant animals show spotty hemorrhage on the kidneys before they die on postnatal day 2 (D). (E-H) Histology of day 2 kidneys from wild type (E,F) and mutant (G,H) stained with H&E. The wild-type genotype is Pax3-cre^tg/+; N2^f/+; the mutant genotype is Pax3-cre^tg/+; N2^f/f. Blue arrows flank the nephrogenic zone; green arrow, proximal tubule; green arrowhead, presumptive renal tubule in mutant; red arrow, glomerulus; yellow arrow, S-shaped body; turquoise arrowhead, collecting duct; D, distal tubule; P, proximal tubule. Scale bars: 1 mm in A-D; 0.1 mm in E-H.