The CRISPR-Cas9 system from Streptococcus pyogenes has been exploited as a programmable RNA-guided DNA-targeting and DNA-editing platform. This evolutionary tool enables diverse genetic manipulations with unprecedented precision and ease. Cas9 is an allosteric enzyme, which is allosterically regulated in conformational activation, target recognition, and DNA cleavage. Here, we outline the underlying allosteric control over the Cas9 complex assembly and targeting specificity. We further review the strategies for mitigating intrinsic Cas9 off-target effects through allosteric modulations and the advances in engineering controllable Cas9 systems that are responsive to external allosteric signals. Future development of highly specific, tunable CRISPR-Cas9 systems through allosteric modulations would greatly benefit applications that require both conditional control and high precision.

中文翻译：

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用于 DNA 靶向和切割的 CRISPR-Cas9 变构调节。


来自化脓性链球菌的 CRISPR-Cas9 系统已被用作可编程 RNA 引导的 DNA 靶向和 DNA 编辑平台。这种进化工具能够以前所未有的精度和轻松性实现多样化的基因操作。 Cas9 是一种变构酶，在构象激活、靶标识别和 DNA 切割中受到变构调节。在这里，我们概述了 Cas9 复合物组装和靶向特异性的基础变构控制。我们进一步回顾了通过变构调制减轻内在 Cas9 脱靶效应的策略，以及响应外部变构信号的工程可控 Cas9 系统的进展。未来通过变构调制开发高度特异性、可调谐的 CRISPR-Cas9 系统将极大有利于需要条件控制和高精度的应用。