Figure 4. Shifts in positional identity by altered β-catenin activity.

(A) Model of predicted changes in segmentation if the gradient of β-catenin activity specifies positional identities in the nephron. Nephrons depicted as spheres representing renal vesicle stage. Dashed line indicates nephron segments. Gradient bar indicates β-catenin activity. (B) Antibody stains against segment specific markers in nephrons with different β-catenin signalling conditions. (C) Proximal, medial, and distal nephron domain-sizes in Control, CHIR, and IWR1 treated kidneys. Mean values and SEMs indicated within bars on graph. (D) qRT-PCR analysis of markers for nephron induction displayed as a heat-map with information displayed in figure. The RNA was isolated after 48 hr of culture from whole kidneys. (E) Antibody stains on nephrons developed in isolated mesenchyme. (F and G) Apc^+/1638N Ctnnb1^Y654/E654 kidneys where Ctnnb1^Y654 is the wild-type allele. Kidneys characterised using anti-Wt1, Jag1, Podxl, Lam, and Cdh1. Arrowheads and boxed area indicate ectopic nephrons in E–F. Dashed lines separate metanephric and mesonephric regions in E–F.

DOI: http://dx.doi.org/10.7554/eLife.04000.020

Figure 4—figure supplement 1. Gradual shifts in positional identity by gentle changes in β-catenin activity.

(A) Typical nephrons for their conditions as cultured at incremental CHIR dosages (0 µM, 0.50 µM, 0.75 µM, 1 µM, 1.25 µM, and 1.5 µM). Dashed lines indicate the axis and lengths of nephron segments. Kidneys stained for Wt1, Jag1, and Cdh1. UB–ureteric bud.

DOI: http://dx.doi.org/10.7554/eLife.04000.021

Figure 4—figure supplement 2. β-catenin activity dosage-dependent phenotypes in series of Apc and Ctnnb1 models.

Kidneys characterised using anti-Wt1, Jag1, Podxl, Lam, and Cdh1. (A) Ctnnb1^Y654/E654 and Ctnnb1^E654/E654, (B) Apc^+/1572T Ctnnb1^Y654/Y654 and Apc ^+/1572T Ctnnb1^Y654/E654. Ctnnb1^Y654 is the wild-type allele. Dashed lines separate metanephric and mesonephric regions.

DOI: http://dx.doi.org/10.7554/eLife.04000.022