Figure 4. Induction of Cre-mediated recombination in various tissues of DiCre×R26R mice.

The presence of recombination is shown by ß-galactosidase expression, as revealed by the blue X-Gal reaction product, in various tissues of adult DiCre×R26R animals ten days after the end of treatment with the inducer (5×10 mg/kg rapamycin i.p.). Bars represent 100 µm. The insert for the liver shows the total absence of recombination in the absence of rapamycin treatment.