Development and application of novel transgenic technology by in vivo RMCE

本研究建立了一个基于Cre-loxP位点特异性重组的受精卵靶向转基因系统，而不是ES细胞。通过重组酶介导的盒交换（RMCE）在受精卵中将两侧具有两个突变loxP位点的转基因整合到种子小鼠（在Rosa 26位点含有loxP位点衍生物）的靶位点中。通过应用这种方法，我们已经建立了共25个转基因株系，显示普遍存在的，强大的，和可重复的转基因表达。我们还证明，敲低小鼠可以很容易地产生PITT利用我们的可重复性和高效的表达系统。

This study established a targeted transgenesis system based on Cre-loxP site-specific recombination in fertilized eggs, but not in ES cells. A transgene, flanked by two mutant loxP sites, was integrated into target loci in the seed mice (containing loxP-site derivatives at Rosa26 locus) by recombinase-mediated cassette exchange (RMCE) in fertilized eggs. By applying this method, we have established a total of 25 transgenic lines showing ubiquitous, strong, and reproducible transgene expression. We also demonstrated that knockdown mice can be readily generated by PITT by taking advantage of our reproducible and highly efficient expression system.