Figure 4: Enhanced BMP signalling in Dullard mutant nephrons.
(a) Immunostaining for p-Smad1/5/8 (blue) shows increased signals in the cortex and outer medulla, but not in the inner medulla, of the Dullard mutant kidneys. Nuclei were counterstained with nuclear fast red. Scale bar, 100 μm. (b) Western blot analysis of p-Smad1/5/8, Smad1/5/8, p-p38 MAPK, and p38 MAPK in kidney extracts from 7-day-old mice. Note the increase in p-Smad1/5/8 in the mutant mice. The data represent typical results from two mice of each genotype in three independent experiments. GAPDH was evaluated as a loading control. (c) p-Smad1/5/8-positive cells (red) overlap with YFP-positive mesenchyme-derived cells (green) in 7-day-old Six2Cre; Dullardflox/flox; R26RYFP mutant kidneys. Scale bar, 10 μm. (d) Immunostaining for Sox9 shows increased signals in the cortex and outer medulla, but not in the inner medulla, of the 7-day-old mutant kidney. Scale bar, 50 μm. (e) Western blot analysis of Sox9 using kidney extracts of 7-day-old mice. Note the Sox9 increase in the mutant mice. The data represent typical results for two mice of each genotype from three independent experiments. GAPDH, glyceraldehyde 3-phosphate dehydrogenase.
