Cre-loxP系统及其衍生系统方法学的研究和在神经科学中的应用

The Cre-loxP system and its derivative systems:methodology research and applications in neuroscience

科研中经常需要在模式生物的特定部位或特定类型细胞内敲入、敲除、敲低或过表达特定的基因以实现对实验自变量的精确调控,这时就需要利用各种转基因小鼠。环化重组酶(cyclization recombinase,Cre)可在无任何辅助因子的作用下与不同形式的loxP(locus X over P1)DNA序列直接结合并相互作用,从而可在特定靶点进行特定基因的敲入、敲除等,具有作用原理简单、空间特异性高、重组效率高等优点而被广泛应用。在Cre-loxP系统基础上衍生出的CreERT2系统(Cre与雌激素受体配体结合域的融合蛋白突变体)以及四环素(tetracycline,Tet)-on/off系统可在空间特异性的基础上补充时间特异性,从而可以使目的基因在特定时间、特定空间发生重组。这种时间、空间的双重特异性在减少对实验动物影响的基础上对于如恐惧记忆、印迹细胞等方面的研究不可或缺,具有广阔的应用前景。

In scientific research,it is often needed to knock in,knock out,knock down,or overexpress a specific gene in model organisms or specific types of cells to achieve precise regulation of experimental independent variables.In this case,various transgenic mice are required.The cyclization recombinase(Cre)can directly interact with different loxP(locus X over P1)DNA sequences without any cofactors to perform specific gene knock-in or knock-out at specific targets.Because of its advantages of simple action principles,high spatial specificity,and high reorganization efficiency,the Cre-loxP system is widely used in scientific research.Furthermore,the CreERT2 system(mutant of the fusion protein of Cre and estrogen receptor ligand binding domain)and the tetracycline(Tet)-on/off system,derived from the Cre-loxP system,have made the recombination of the target gene occur in temporalspecificity on the basis of spatial-specificity.This dual specificity of time and space is indispensable for research in specific directions such as fear memory and engram cells on the basis of reducing the impacts on experimental animals.Therefore,these derived systems have broad application prospects.