The ability to create DNA double-strand breaks (DSBs) at specified genomic locations, which then stimulate the cell's naturally occurring DNA repair processes, has introduced intriguing possibilities for genetic modification. Zinc finger nucleases (ZFNs) are designed restriction enzymes consisting of a nonspecific cleavage domain fused to sequence-specific DNA binding domains. ZFN-mediated DSB formation at endogenous genomic loci followed by error-prone non-homologous end joining (NHEJ) repair can result in gene-specific mutations via nucleotide base pair insertions or deletions. Similarly, specific DNA sequence modifications can be made by providing donor DNA templates homologous to sequences flanking the cleavage site via homology-directed repair (HDR). Targeted deletions of intervening DNA sequence can be obtained by ZFNs used to create concurrent DSBs. Site-specific transgene integration into ZFN-induced DSBs is possible via either NHEJ or HDR. Genome editing can be used to enhance our basic understanding of plant gene function as well as modify and improve crop plants. As with conventional plant transformation technology, the efficiency of genome editing is absolutely dependent on the ability to initiate, maintain, and regenerate plant cell and tissue cultures.

中文翻译：

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通过设计的锌指核酸酶在植物中进行基因组编辑。

在指定的基因组位置产生DNA双链断裂（DSB）的能力，然后刺激细胞天然发生的DNA修复过程，为基因修饰引入了有趣的可能性。锌指核酸酶（ZFN）是设计的限制性酶，由与序列特异性DNA结合结构域融合的非特异性切割结构域组成。ZFN介导的DSB在内源基因组位点形成，然后容易出错的非同源末端连接（NHEJ）修复可通过核苷酸碱基对的插入或缺失导致基因特异性突变。同样，通过提供与同源位点修复（HDR）的切割位点侧翼序列同源的供体DNA模板，可以进行特定的DNA序列修饰。插入DNA序列的靶向缺失可以通过用于创建并发DSB的ZFN获得。通过NHEJ或HDR，可以将位点特异性转基因整合到ZFN诱导的DSB中。基因组编辑可用于增强我们对植物基因功能的基本了解以及修饰和改良农作物。与常规植物转化技术一样，基因组编辑的效率绝对取决于启动，维持和再生植物细胞和组织培养物的能力。