摘要
基因组编辑技术利用人工核酸酶以精准和可预测的方式来快速改造和修饰基因组,加速了基础研究和植物育种的进程。近年来兴起的II型CRISPR/Cas9基因组编辑技术成功应用于多种动植物中。CRISPR/Cas9系统在可定制的小型非编码RNA的指导下定向切割基因组DNA双链,并通过非同源末端连接(NHEJ)和同源重组(HDR)机制进行基因修饰,从而实现基因组靶标基因的定点改造。本综述介绍了CRISPR/Cas系统的结构及作用原理,讨论了CRISPR/Cas9系统的靶点效率、脱靶效应以及Cas9突变体的筛选,并对CRISPR/Cas9系统的表观遗传调控进行了分析。最后我们详细阐述了CRISPR/Cas9技术在植物中的最新应用进展,并对CRISPR/Cas9系统的发展和应用前景进行了展望,希望为开展植物基因组编辑方面的研究工作提供参考。
Targeted genome editing using artificial nucleases has the potential to accelerate basic research as well as plant breeding by providing the means to modify genomes rapidly in a precise and predictable manner.Until recently, the type II CRISPR/Cas9 genome editing technology has been successfully applied to many animal and plant species. The CRISPR/Cas9 system allows targeted cleavage of genomic DNA guided by a customizable small non-coding RNA, resulting in gene modifications by both non-homologous end joining(NHEJ)and homology-directed repair(HDR) mechanisms. In this review, we introduced the structure and mechanism of CRISPR/Cas system, discussed the target efficiency, off-target effect and the screening of Cas9 mutants in CRISPR/Cas9 system, and analyzed the epigenetic regulation of CRISPR/Cas9 system. Finally, we summarized the latest development and applications of CRISPR/Cas9 technology in plants, as well as highlight challenges and future directions of CRISPR/Cas9 system, which would provide a reference for the research in plant genome editing.
引文
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