Tg(Wap-rtTA-cre)10Whl

Sequence encoding reverse tetracycline-controlled transactivator (rtTA) was placed under control of the whey acidic protein promoter and in cis configuration with sequence encoding cre recombinase adjoined to an rtTA-inducible CMV promoter. Initial reporter analysis showed cre activity to be completely doxycycline dependent and restricted to the mammary epithelial cells. In contrast, subsequent activity analysis in J:90247 showed doxycycline independent cre activity in a variety of tissues including the mammary gland, brain, liver, and spleen; putatively due to a modification of the transgene and/or the unstable nature of transgene copy number. (J:69330)