Fig. 1. Disruption of Frs2 alleles in prostate epithelium. (A) Schematic of the floxed Frs2 alleles for conditional disruption. The genomic DNA containing coding exons 1-5 and adjacent introns is shown. Dashed boxes indicate non-coding exon sequence. The primers for PCR genotyping are indicated by arrows. Primers f1 and f2 amplify a 319 bp fragment from the floxed Frs2 allele. Primers f1 and f3 amplify a 261 bp fragment from the Frs2-null allele; no amplification from wild-type alleles. (B) PCR genotyping for the Frs2 conditional-null alleles. Genomic DNAs extracted from each prostatic lobe of 4-week-old mice were analyzed by PCR using the primers illustrated in A. (C) Total RNAs were extracted from prostates of different ages, and Frs2 expression was assessed by real-time RT-PCR. The data were normalized to β-actin loading controls and are expressed as mean±s.d. of at least three independent experiments. Note that Frs2 alleles were intact in the stromal compartment, which is likely to account for the basal level of Frs2 expression in Frs2^cn prostates. Representative data from dorsolateral prostate are shown. (D) In situ hybridization of Frs2 expression in prostates. Enlarged image of boxed area shown on the right. Note that the expression was diminished in the epithelium of Frs2^cn prostates and mature control prostates. Arrows indicate basal cells. AP, anterior prostate; DLP, dorsolateral prostate; VP, ventral prostate; M, myristylation site; PTB, phosphotyrosine-binding site; f, Frt element; p, loxP element; F/F, homozygous Frs2^flox mice; CN, Frs2^cn mice.