Safran Michal, Kim William Y, Kung Andrew L, Horner James W, DePinho Ron A, Kaelin William G
Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Mol Imaging. 2003 Oct;2(4):297-302. doi: 10.1162/15353500200303154.
Conditional alleles containing LoxP recombination sites, in conjunction with Cre recombinase delivered by a variety of means, allows for spatial and temporal control of gene expression in mouse models. Here we describe a mouse strain in which a luciferase (Luc) cDNA, preceded by a LoxP-stop-LoxP (L-S-L) cassette, was introduced into the ubiquitously expressed ROSA26 locus. Mouse embryo fibroblasts derived from this strain expressed luciferase after Cre-mediated recombination in vitro. ROSA26 L-S-L-Luc/+ mice expressed luciferase in a diffuse or liver-restricted pattern, as determined by noninvasive, bioluminescent imaging, when crossed to transgenic mice in which Cre was under the control of a zygotically expressed (EIIA-Cre), or a liver-restricted (albumin-Cre), promoter, respectively. Organ-specific luciferase expression was also seen after intraparenchymal administration of an adenovirus encoding Cre. The ROSA26 L-S-L-Luc/+ strain should be useful for characterizing Cre mouse strains and for following the fate of cells that have undergone Cre-mediated recombination in vivo.
含有LoxP重组位点的条件性等位基因，与通过多种方式递送的Cre重组酶相结合，能够在小鼠模型中实现基因表达的时空控制。在此，我们描述了一种小鼠品系，其中一个带有LoxP-stop-LoxP（L-S-L）盒的荧光素酶（Luc）cDNA被引入到广泛表达的ROSA26基因座中。源自该品系的小鼠胚胎成纤维细胞在体外经Cre介导的重组后表达荧光素酶。当与Cre分别受合子表达启动子（EIIA-Cre）或肝脏特异性启动子（白蛋白-Cre）控制的转基因小鼠杂交时，通过非侵入性生物发光成像确定，ROSA26 L-S-L-Luc/+小鼠以弥漫性或肝脏限制性模式表达荧光素酶。在实质内给予编码Cre的腺病毒后，也观察到了器官特异性荧光素酶表达。ROSA26 L-S-L-Luc/+品系应有助于鉴定Cre小鼠品系，并追踪体内经历Cre介导重组的细胞的命运。
