Generation of a Wt1 conditional deletion, nuclear red fluorescent protein reporter allele in the mouse.

A Wt1 conditional deletion, nuclear red fluorescent protein (RFP) reporter allele was generated in the mouse by gene targeting in embryonic stem cells. Upon Cre-mediated recombination, a deletion allele is generated that expresses RFP in a Wt1-specific pattern. RFP expression was detected in embryonic and adult tissues known to express Wt1, including the kidney, mesonephros, and testis. In addition, RFP expression and WT1 co-localization was detected in the adult uterine stroma and myometrium, suggesting a role in uterine function. Crosses with Wnt7a-Cre transgenic mice that express Cre in the Müllerian duct epithelium activate Wt1-directed RFP expression in the epithelium of the oviduct but not the stroma and myometrium of the uterus. This new mouse strain should be a useful resource for studies of Wt1 function and marking Wt1-expressing cells.