Fig. 3. Colony-forming progenitors exist in the Sall1-GFP^high subpopulation of the metanephros. (A,B) Cryosections of metanephros of Sall1-GFP knock-in mouse (A: E11.5; B: E17.5). Blue: DAPI. (C) Metanephros contains three subpopulations (Sall1-GFP^high, Sall1-GFP^low and Sall1-GFP^negative). The percentages of the subpopulations at each fetal stage are shown. Figures are the average of five independent experiments. (D) RT-PCR analysis of three subpopulations included in E11.5 mesenchyme. (E) Numbers of colonies in each subpopulation derived from E11.5 mesenchyme, E14.5 and E17.5 metanephros. The numbers of colony were counted after 20-day culture. The graph shows the average of five independent experiments. ub, ureteric bud; mes, mesenchyme; c, C-shaped body; rt, renal tubule. Scale bars: 50 µm.