Rohlmann A, Gotthardt M, Willnow T E, Hammer R E, Herz J
Department of Molecular Genetics, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas 75235, USA.
Nat Biotechnol. 1996 Nov;14(11):1562-5. doi: 10.1038/nbt1196-1562.
Transgenic and knockout mice have proven invaluable tools for analyzing physiologically relavant functions of numerous genes. In some cases, however, pleiotropic effects that result from a variable requirement for a particular gene in different tissues, cell types, or stages of embryonic development may complicate the analysis due to a complex phenotype or embryonic lethality. The loxP/Cre-mediated recombination system, which allows tissue-specific gene targeting in the mouse, can be used to overcome these problems. A limitation of current methods is that a mouse carrying a loxP-tagged gene must be crossed with a transgenic mouse expressing the Cre recombinase in an appropriate tissue to obtain the desired gene rearrangement. We have used recombinant adenovirus carrying the Cre recombinase to induce virtually quantitative somatic cell gene disruption in the liver. The targeted gene was the multifunctional low-density lipoprotein receptor-related protein (LRP), a cell surface receptor for alpha 2-macroglobulin and other ligands. Transient expression of Cre following adenoviral infection produced the predicted gene rearrangement, functionally inactivating LRP in the liver. Rearrangement occurred within 6 days after infection and remained stable for at least 28 days. The results demonstrate the suitability of adenoviral Cre gene transfer to induce long-term, quantitative, and temporally controlled gene disruption in the mouse.
转基因小鼠和基因敲除小鼠已被证明是分析众多基因生理相关功能的宝贵工具。然而，在某些情况下，由于特定基因在不同组织、细胞类型或胚胎发育阶段的需求不同而产生的多效性效应，可能会因复杂的表型或胚胎致死性而使分析变得复杂。loxP/Cre介导的重组系统可实现小鼠组织特异性基因靶向，可用于克服这些问题。当前方法的一个局限性在于，携带loxP标记基因的小鼠必须与在适当组织中表达Cre重组酶的转基因小鼠杂交，才能获得所需的基因重排。我们使用携带Cre重组酶的重组腺病毒在肝脏中诱导几乎定量的体细胞基因破坏。靶向基因是多功能低密度脂蛋白受体相关蛋白（LRP），它是α2巨球蛋白和其他配体的细胞表面受体。腺病毒感染后Cre的瞬时表达产生了预测的基因重排，在功能上使肝脏中的LRP失活。重排在感染后6天内发生，并至少稳定28天。结果表明腺病毒Cre基因转移适用于在小鼠中诱导长期、定量和时间可控的基因破坏。
