Tg(Gad1-cre,-lacZ)1Mini

A cassette consisting of a hybrid intron, the cre-IRES-lacZ sequence and a downstream frt-flanked neo selection marker (in reverse orientation) was inserted into the first coding ATG of the Gad1 locus in a BAC clone (RPC123-118N13) by ET recombination in bacteria. After selection of correctly recombined cells, Flp expression excised the neo cassette. The circular BAC DNA construct was injected into pronuclei of oocytes. Offspring of founder mice were tested by X-gal staining for presence of a functional lacZ cassette. Staining was weak possibly due to low efficiency of the IRES site. Cre mediated EYFP or EGFP expression was used to assess recombination in crosses with reporter mice. (J:195054)