Trh^{tm1.1(cre)Mjkr}

Using recombineering methods, a selection cassette containing an internal ribosomal entry sequence (IRES) linked to cre and an frt-flanked kanamycin gene was inserted immediately downstream of the stop codon in exon 2 of the Trh gene in a BAC. This construct was used to isolate a targeting plasmid with the cre-kanamycin cassette with upstream and downstream Trh homology arms. ES cells were targeted and used for blastocyst injection. Chimeras were bred for germline transmission. The selection marker was excised by breeding to Flp deleter animals, however, a partial neo (164 bp fragment of the 3' end of neo) remains between the IRES-Cre and polyA sequences. (J:101977, J:207472)