Fig. 2. Foxa1 regulates prostate ductal morphogenesis. (A) Upper panels: urogenital organs (lateral, left, and dorsal, right, views) dissected from P1 pups. The bladder was removed as indicated by broken lines. Lower panels: prostate rudiments (asterisks) and seminal vesicle (SV) were grafted as renal rescue tissue. (B-D) Upper panels: 8-week-old rescued tissues, with indicated genotypes, developed in the host renal capsules. SVs are circled with broken lines. Rescued Foxa1^–/– prostate (asterisk in D) is smaller than controls upon comparison after fine dissection (lower panels). (E-G) ß-Galactosidase staining on 8-week-old rescued prostates. (H) Twelve-week-old tissue recombinants derived from wild-type (left) or Foxa1^–/– (right) epithelium that was recombined with E18 rUGM. (I) The Foxa1^–/– recombinants have significantly lower weights than controls (n=3, P<0.01). (J-K) Hematoxylin and Eosin staining of 4-week-old rescued Foxa1^–/– and Foxa1^+/+ VPs. (L,M) AR staining. (N,O) High magnification views of regions framed in L and M (arrowheads). (P,Q) Toluidine Blue staining on 1 µm thin section of 12-week-old rescued Foxa1^–/– and wild-type VPs. (R,S) E-cadherin staining (red) on 12-week-old rescued Foxa1^–/– and wild-type VPs. Foxa1-null epithelial cell polarity is disrupted (arrowheads). (T,U) Hematoxylin and Eosin staining of 12-week-old tissue recombinants from Foxa1^–/– and control epithelium.