Gm10822^{Tn(pb-CAG-tdTomato,-cre)Cot2Zhu}

The transposon containing a CAG (CMV enhancer chicken beta Actin promoter beta-Globin first intron) promoter, F3 (an FRT spacer mutant), tdTomato, F13 (another FRT spacer mutant), second F3, Cre-IRES-GFP, second F13 followed by polyadenylation signal flanked by piggyBac-specific left and right terminal sequences was co-injected with a piggyBac-containing transgene to mobilize the transposon. CAG promoter drives constitutive expression of either the tdTomato marker or the Cre recombinase upon Flp/FRT-mediated recombination. The Cre cDNA is tagged at its 3 end with iresGFP for lineage tracing of Cre expression. The Tomato and Cre coding sequences are flanked by two distinct pairs of FRT sites with the internal FRT sites hopping over each other. Flp-induced recombination between either of the FRT pairs results in deletion of either Tomato or the Cre-GFP cassette, resulting in mutually exclusive expression of either Cre-GFP or tdTomato, respectively. Lines with single-copy integration events outside any essential genes were screened by crossing the founder mouse to a piggyBac transposase expression strain and screened for new insertion events in the F2 generation. Three independent insertional events on separate chromosomes were identified and one Line named Cot2 inserted into the intron of the GM10822 locus (Ch2: 76405893 Ensemble version 99) in cis orientation was established for further analysis. (J:297537)