Figure 2. Localization of GFRα1and RET in the UGS and developing prostate.

Time course of Gfrα1 mRNA (A) and Ret mRNA levels (B) in the UGS and developing prostate (E14.5 to P5) of male mice was determined by QPCR analysis. Relative quantification of Gfrα1 and Ret mRNAs is shown using the mean and SEM (n = 6) in log2 scale. Gfrα1 and Ret mRNA levels were highest in the early stages of prostate development. C, UrM and UrE were separated from E15.5 male UGSs, and immunoblot analysis shows that GFRα1 protein is localized in the UrM and UrE prior to prostate development in vivo, whereas RET expression is localized to the UrM. Adult prostate tissue was dissociated, and immunoblot analysis of PrS and PrE revealed that GFRα1 and RET expression is restricted to adult stromal cells. The clean separation of the mesenchyme/stroma and epithelium is supported by immunodetection of mesenchymal/stromal vimentin and epithelial keratins. D, Immunohistochemistry revealed the localization of RET protein expression (red) in the UGS and during prostate development in vivo (E15.5 to P0 and the ventral lobe of P90 adult prostate). DAPI-stained nuclei (blue) identify all cells in the sections, and immunodetection of keratins (green) has been shown to identify the UrE as well as the ventral and dorsal prostatic epithelium (VPE and DPE). RET is expressed in the VMP and to a lesser extent in the PUM of the UGS and developing prostate. The boundaries between the PUM and UrE and the PrS and PrE have been traced (dashed white line), and the VMP has been labeled. The scale bars represent 100 μm.