Figure 3.

Ureteric budding is disrupted in Hox11 mutants. Hematoxylin and eosin-stained sections (5 μm) of paraffin-embedded E11.5 embryos. W, Wolffian duct. Red arrows denote metanephric blastema. (A) Normal ureteric budding into the blastema of a control embryo. This process appears to occur normally in double mutant embryos (Hoxa11/Hoxd11 double mutant shown in B). The green arrow in panel C shows the right ureteric bud of a five-allele mutant embryo. This bud never makes contact with the metanephric blastema, but can be followed through sections traversing an indirect path around it. (D) A triple mutant embryo. No ureteric bud is ever formed in these embryos.