Overexpression of complementary DNA represents the most commonly used gain-of-function approach for interrogating gene functions and for manipulating biological traits. However, this approach is challenging and inefficient for multigene expression due to increased labour for cloning, limited vector capacity, requirement of multiple promoters and terminators, and variable transgene expression levels. Synthetic transcriptional activators provide a promising alternative strategy for gene activation by tethering an autonomous transcription activation domain (TAD) to an intended gene promoter at the endogenous genomic locus through a programmable DNA-binding module. Among the known custom DNA-binding modules, the nuclease-dead Streptococcus pyogenes Cas9 (dCas9) protein, which recognizes a specific DNA target through base pairing between a synthetic guide RNA and DNA, outperforms zinc-finger proteins and transcription activator-like effectors, both of which target through protein-DNA interactions ¹ . Recently, three potent dCas9-based transcriptional activation systems, namely VPR, SAM and SunTag, have been developed for animal cells ^2-6 . However, an efficient dCas9-based transcriptional activation platform is still lacking for plant cells ^7-9 . Here, we developed a new potent dCas9-TAD, named dCas9-TV, through plant cell-based screens. dCas9-TV confers far stronger transcriptional activation of single or multiple target genes than the routinely used dCas9-VP64 activator in both plant and mammalian cells.

中文翻译：

---

一种有效的 Cas9 衍生基因激活剂，适用于植物和哺乳动物细胞。

互补 DNA 的过表达代表了用于询问基因功能和操纵生物学特征的最常用的功能获得方法。然而，由于克隆劳动力增加、载体容量有限、需要多个启动子和终止子以及可变的转基因表达水平，这种方法对多基因表达具有挑战性且效率低下。合成转录激活剂通过可编程的 DNA 结合模块将自主转录激活结构域 (TAD) 连接到内源基因组位点的预期基因启动子，从而为基因激活提供了一种有前景的替代策略。在已知的定制 DNA 结合模块中，核酸酶死亡的化脓性链球菌 Cas9 (dCas9) 蛋白，¹ . 最近，已经为动物细胞^2-6开发了三种有效的基于 dCas9 的转录激活系统，即 VPR、SAM 和 SunTag 。然而，植物细胞仍然缺乏基于 dCas9 的高效转录激活平台^7-9。在这里，我们通过基于植物细胞的筛选开发了一种新的强效 dCas9-TAD，名为 dCas9-TV。与植物和哺乳动物细胞中常规使用的 dCas9-VP64 激活剂相比，dCas9-TV 对单个或多个靶基因的转录激活作用要强得多。