Generation of Pax8-CreER^T2 transgenic mice.

(A) The previously published pPax8-rtTA plasmid [7] is shown in the top panel. The CreER^T2 coding sequence followed by a polyadenylation signal (pA) was used to replace the rtTA sequence of pPax8-rtTA and generate plasmid pPax8-CreER^T2 (bottom panel) containing 4.3kb of upstream regulatory sequence, complete exon 1 and intron 1, part of exon 2 and 0.8kb of intron 2 of the murine Pax8 gene. (B) FISH analysis of metaphase spreads using pPax8-CreER^T2 as probe (green) maps the integration site to chromosome 6 (arrowheads). A weaker signal from the endogenous Pax8 locus can be detected on chromosome 2 (arrows).