Egr1^{tm1.1(cre/ERT2)Jglt}

A targeting vector consisting of a Cre/ERT2 cassette and a neomycin resistance gene flanked by FRT sequences were inserted into the transcription start site of the Egr1 gene in a bacterial artificial chromosome (BAC, clone RP23-70M6) that contained the entire mouse Egr1 gene with 95 kb 5 upstream and 86 kb downstream regions was used for homologous recombination in the ES cells. After selection and cloning of the ES cells, the neomycin resistance gene was removed by flipase and the resulting transgenic ES cells were injected into agouti blastocysts to obtain chimeric mice. Two lines (U62-2 and U62-7) were obtained, and U62-2 line was established and used for the studies. (J:335757)