Endothelial-Specific Cre Mouse Models

Abstract

The field of vascular biology has gained enormous insight from the use of Cre and inducible Cre mouse models to temporally and spatially manipulate gene expression within the endothelium. Models are available to constitutively or inducibly modulate gene expression in all or a specified subset of endothelial cells. However, caution should be applied to both the selection of allele and the analysis of resultant phenotype: many similarly named Cre models have divergent activity patterns while ectopic or inconsistent Cre or inducible Cre expression can dramatically affect results. In an effort to disambiguate previous data and to provide a resource to aid appropriate experimental design, here we summarize what is known about Cre recombinase activity in the most widely used endothelial-specific Cre and Cre/ERT2 mouse models.

Keywords: endothelial cells; gene expression; mice; phenotype; recombinases.

Figure 1. A direct comparison of the embryonic expression pattern and intensity of the Cre reporter R26R:lacZ when crossed with different EC-specific Cre alleles on the C57/Bl6 background.

Embryonic age was established from date of plug in mother, all embryos were fixed, stained and sectioned using identical conditions across each age group as previously described. For tamoxifen administration, 100μl tamoxifen (10mg/ml in a 10:1 solution of peanut oil and 100% ethanol) was administered orally via gavage on two consecutive days as indicated, and embryos taken 48 hours after last dose. When two embryos for the same allele are shown, they are littermates. E=embryonic day, da=dorsal aorta, cv=cardinal vein, end=endocardial lining of heart