Tg(Tbx6-cre/ERT2)5769Fan

A region (containing the Tbx6 enhancer and promoter fragment) -2.5 kb upstream and +25 bp downstream of the Tbx6 transcriptional start site was amplified from a BAC template (RP24-239G12). This fragment was cloned 5' to a cre/ERT2 expression cassette in a plasmid. The linearized, purified transgene was injected into pronuclei of (C57BL/6 x DBA/2)F1 embryos. 16 founders cre-positive founders were identified by PCR. Each founder was bred to ROSA-lacz reporter mice and pregnant mice were treated with tamoxifen. 6 lines were sterile, lacked cre activity or showed ubiquitous activity in all mesodermal tissues. 4 lines showed mosaic activity in the presomitic mesoderm (represented by line 5578). The remaining 6 lines had tightly-regulated tamoxifen-inducible cre activity, with line 5679 being further characterized due to tamoxifen-regulated PSM activity. (J:185483)