A transgenic Tbx6;CreERT2 line for inducible gene manipulation in the presomitic mesoderm.

The rhythmic segmentation process of the presomitic mesoderm (PSM) orchestrates the formation of somites, the fundamental units for the vertebrate axial body plan. To aid the investigation of molecular components governing the conversion from PSM into somites, we generated a transgenic mouse line that expresses a tamoxifen (tmx) inducible CreER(T2) under the control of a 2.5 kb enhancer element of Tbx6, a gene essential for PSM formation and somite patterning. Combined with Cre reporters, this Tbx6;CreER(T2) line displays robust tmx-inducible Cre activity in the PSM at various embryonic stages. This tool should be useful for studying gene function during somitogenesis by either conditional inactivation or mis-expression, and potentially coupled with cell marking.