Purpose of review

The Cre recombinase/loxP (Cre/loxP) system has emerged as a useful tool in genetic manipulations. Generally, any DNA sequence of interest can be deleted when flanked with loxP sites. The conditional (timely or spatially controlled) expression of Cre recombinase enables to determine, where (e.g. in which cell type or tissue) and when (at which time of life or of developmental stage of cells/tissues) the deletion of the floxed DNA sequence should occur. Therefore, two mouse lines are usually needed for conditional site-specific genome modification. This review aims to provide a general overview of the Cre/loxP system, elaborate on the different keratinocyte specific knockout mice used to study gene function in keratinocytes, and finally demonstrate the generation of a conditional knockout mice.

Recent findings

Knockout mice have been efficient and powerful approach to understand the functions of specific genes in development and physiological homeostasis. However, deletion of the specific genes which are concerned in stages of development induces to embryonic lethality. To overcome this obstacle, Cre/loxP system has been used to delete a gene in a specific organ or tissue, or at a specific embryonic developmental stage. Conditional knockout mice have allowed extensive research of the epidermis and helped elucidate roles of many gene functions in keratinocytes.

中文翻译：

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通过Cre–loxP重组系统的角质形成细胞特异性基因敲除小鼠模型

审查目的

Cre重组酶/ loxP（Cre / loxP）系统已经成为基因操作中的有用工具。通常，与loxP位点侧翼时，任何感兴趣的DNA序列都可以删除。Cre重组酶的条件性（时间或空间控制）表达能够确定在何处（例如，在哪种细胞类型或组织中）以及何时（在生命或生命的时间或细胞/组织的发育阶段）删除该脱氧核糖核酸序列应该发生。因此，通常需要两条小鼠系来进行条件位点特异性基因组修饰。这篇综述旨在提供Cre / loxP系统的一般概述，详细介绍用于研究角质形成细胞基因功能的不同角质形成细胞特异性敲除小鼠，并最终证明条件性敲除小鼠的产生。

最近的发现

敲除小鼠已经成为了解特定基因在发育和生理稳态中功能的有效且有力的方法。然而，在发育阶段中涉及的特定基因的缺失引起胚胎致死性。为克服这一障碍，已使用Cre / loxP系统删除特定器官或组织中或特定胚胎发育阶段的基因。有条件的基因敲除小鼠已经允许对表皮进行广泛的研究，并有助于阐明角质形成细胞中许多基因功能的作用。