Cartpt^{tm1.2(cre/ERT2)Hhz}

The targeting vector was designed to replace the CART coding exons with the mouse Cartpt cDNA fused to the original CART gene at the initiation codon, which is followed by the insertion of a flippase (Flp) recombinase-recombination target (FRT)-flanked neomycin selection cassette. A cassette carrying the tamoxifen-inducible Cre-recombinase gene followed by an internal ribosome entry site (IRES) that drives the expression of the mCherry red fluorescence reporter gene was inserted. Chimeric offspring were bred with a germline Flp-recombinase mouse line to remove the neomycin cassette. LoxP sites were placed immediately upstream of the initiation codon of the CART and Cre genes respectively, which allows the replacement of the CART gene by Cre. Homozygous mice were then crossed with mice that expressed Cre specifically in the oocytes, resulting in a rearrangement that combines the inducible Cre gene with the endogenous CART promoter. (J:333645)