Id1^{tm2(cre/ERT2)Bene}

An encephalomyocarditis virus internal ribosomal entry site (EMCV IRES) and a tamoxifen-inducible recombinase cre/ERT2 coding sequence were inserted after the Id1 gene coding sequence. An FRT-Neo-FRT cassette was inserted after the IRES-cre/ERT2 sequence and before the 3' untranslated region. The Id1 protein and creERT2 protein are translated from a bicistronic messenger RNA with the endogenous polyadenylation sequence. CY2.4 ES cells (albino C57BL/6 derivation) were used for targeting. Southern blot positive clones were injected into co-isogenic B6J blastocyts. Positive chimeras were bred to albino B6J females. Albino pups were genotyped by PCR, and positive pups were bred to B6 ACTB::FLPE mice (Artemis Pharamaceuticals) to excise the Neo cassette in vivo. (J:154023)