Fig. 4.

Models of UGS development in p63–/– and WT mice. (A) In the absence of p63, the UGS endoderm maintains the capacity to differentiate toward multiple lineages and develops glandular structures lined by both prostate luminal cells and extraprostatic (i.e., intestinal) epithelium. (B) During normal prostate organogenesis, prostate buds are composed of p63-positive basal progenitor cells, which give rise to all of the cell types that compose the mature prostate epithelium. p63 expression is required in these progenitor cells to restrict their differentiation potential to the prostate cell lineage.