Egfr^tm1Arge

LoxP sites were inserted to flank exons 9 and 10 of the gene. A LacZ reporter with a nuclear localization signal was inserted upstream of the first LoxP site and exon 9. After exon 10, a STOP sequence and a neo selection cassette were inserted preceding the LoxP site, and a CMV minimal promoter was inserter after the loxP site. These insertions were reported to interfere with normal expression of the gene and resulted in a null allele. Upon Cre-mediated excision, exons 9 and 10, the STOP sequence and the selection cassette are removed, juxtaposing the CMV promoter and the nls-LacZ reporter so that reporter expression provides a readout of excision in the tissue. (J:60711)