Fig. 2
The developing and regenerating mesonephros contain proliferating basophilic clusters that express wt1b. A–D: Larvae (A,B) and adult fish with kidney damage (C,D) were injected with BrdU and serial sections were alternately stained with H+E and anti-BrdU by immunohistochemistry. This shows that the developing mesonephros (A,B) and the regenerating adult mesonephros (C,D) both have basophilic clusters with BrdU+ cells (arrows). E,F: Tg(wt1b:GFP) transgenic fish with kidney damage were also injected with BrdU and stained similarly to C,D. This shows that basophilic clusters in the regenerating kidney also express wt1b-GFP (arrows). PT: pronephric tubule; MT: mesonephric tubule; H+E: hematoxylin and eosin.