Snap25^{tm2.1(cre)Hze}

The targeting vector contained, from 5' to 3', a partial Snap25 sequence spanning intron 6 through intron 7, an frt3 site within Snap25 intron 7, a partial Snap25 exon 8 sequence up to and including the endogenous stop codon, an internal ribosome entry site 2 (IRES2) sequence, a cre recombinase gene, a bovine growth hormone polyA sequence, an AttB site, a PGK promoter-Neomycin resistance gene-PGK polyA cassette, an frt5 site, an mRNA splice acceptor, the 3' portion of the hygromycin gene with SV40 late polyA signal, and an AttP site. This construct was electroporated into G4 embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts. Chimeric mice were bred to PhiC31-expressing mice to remove the AttB/AttP-flanked sequences (PGK-Neo-polyA::frt5::RNA splice acceptor::3'hygro-polyA) and replace it with the recombined AttB/AttP site (AttL). The resulting Snap25-IRES2-Cre-D mice were bred with C57BL/6J wildtype mice to remove the PhiC31 transgene. (J:146821, J:220523)