Fig. 3.

Several CreER^T2 lines are basally active and lead to reporter gene activation in vivo in the absence of Tamoxifen. a Confocal images of the ear skin vasculature of mice carrying the Ai14 reporter alone or in combination with one of the following CreER^T2 lines: Prox1 (expressed in lymphatic endothelial cells, LEC), Pdgfb (expressed in LEC and blood endothelial cells, BEC) or Cdh5 (expressed in LEC and BEC). Widespread tdTomato expression, a consequence of Tamoxifen independent recombination of the Ai14 reporter, is observed in all CreER^T2 lines, but it does not occur in the absence of a CreER^T2 driver in mice that only carry the Ai14 reporter. BEC and LEC are visualized with a CD31 antibody (red) and LEC are stained with a Lyve1 antibody (blue). tdTomato expression from the Ai14 reporter is shown in green. Scale bars indicate 500 μm. b Higher resolution images from the pictures in a). Scale bars indicate 200 μm