A Probasin-MerCreMer BAC allows inducible recombination in the mouse prostate.

Tissue-specific transgene expression in the prostate epithelium has previously been achieved using short prostate-specific promoters, rendering transgenic mouse lines susceptible to integration site-dependent effects. Here we demonstrate the applicability of bacterial artificial chromosome (BAC) technology to transgene expression in the prostate epithelium. We present mouse lines expressing an inducible Cre protein (MerCreMer) under the control of regulatory elements of the probasin gene on a BAC. These mouse lines show high organ specificity, high transgene expression in anterior, dorsal and lateral prostate lobes, no background Cre recombination using a reporter strain and adjustable amounts of Cre-induced recombination upon tamoxifen induction. Together with two recently reported transgenic lines expressing the Cre-ERT2 protein from small prostate-specific promoters, these mouse lines will be useful in research focused on prostate-specific disorders such as benign hyperplasia or cancer.