Mammary Specific Expression of Cre Recombinase Under the Control of an Endogenous MMTV LTR: A Conditional Knock-Out System.

摘要

This project was designed to test expression of ore recombinase directed by the endogenous Mtv-l7 locus. The hypothesis of the project was to develop a novel and useful breast cancer model using the tissue-specific expression of the Mtv-l7 locus, which had previously been shown by our lab to express only in the mammary gland. We proposed targeting the ore recombinase gene to the Mtv-l7 envelope gene, so that this enzyme would only be expressed in mammary epithelial cells. During the funding period, we were able to create ES cells that had the ore recombinase gene targeted to the Mtv-l7 locus. However, we were unable to generate transgenic mice that retained this targeted gene in their germline. We were therefore unable to carry out the rest of the project, which was to cross the cre-recombinase-containing mice with mice that had the p53 gene flanked by the loxP target sequences, thereby creating mammary gland- specific loss of the p53 gene. We were thus unable to test our mammary tumor model.