Laboratory of Biotechnology, Federal Scientific Center of the East Asia Terrestrial Biodiversity, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, 690022, Russia.
The School of Natural Sciences, Far Eastern Federal University, Vladivostok, 690090, Russia.
Appl Microbiol Biotechnol. 2020 Mar;104(5):2125-2135. doi: 10.1007/s00253-020-10355-y. Epub 2020 Jan 14.
Recent research has shown that plants can uptake long dsRNAs and dsRNA-derived siRNAs that target important genes of infecting fungi or viruses when applied on the surface of plant leaves. The external RNAs were capable of local and systemic movement inducing plant resistance against the pathogens. Few studies have been made for plant gene regulation by foliar application of RNAs. In this study, several types of ssRNA and siRNA duplexes targeting the neomycin phosphotransferase II (NPTII) transgene were in vitro-synthesized and externally applied to the leaf surface of 4-week-old transgenic Arabidopsis thaliana plants. External application of the synthetic NPTII-encoding siRNAs down-regulated NPTII transcript levels in transgenic A. thaliana 1 and 7 days post-treatment with a higher and more consistent effect being observed for siRNAs methylated at 3' ends. We also analyzed the effects of external NPTII-encoding dsRNA precursors and a dsRNA-derived heterogenous siRNA mix. Digestion of the NPTII-dsRNA to the heterogeneous siRNAs did not improve efficiency of the transgene suppression effect. Key Points• Foliar application of siRNAs down-regulated a commonly used transgene in Arabidopsis. • A more consistent effect was observed for methylated siRNAs. • The findings are important for development of plant gene regulation approaches.
最近的研究表明，当将长 dsRNA 和靶向侵染真菌或病毒的重要基因的 dsRNA 衍生的 siRNA 施加于植物叶片表面时，植物可以摄取这些外源性 RNA。这些外源性 RNA 能够在局部和系统水平上移动，从而诱导植物对病原体产生抗性。目前，关于通过叶面施用 RNA 来调节植物基因的研究还很少。在这项研究中，我们体外合成了几种靶向新霉素磷酸转移酶 II（NPTII）转基因的 ssRNA 和 siRNA 双链体，并将其施加于 4 周龄转基因拟南芥叶片的表面。体外施加合成的 NPTII 编码 siRNA 可下调转基因拟南芥中 NPTII 的转录本水平，在处理后 1 天和 7 天观察到 3' 末端甲基化的 siRNA 表现出更高和更一致的效果。我们还分析了外源性 NPTII 编码 dsRNA 前体和 dsRNA 衍生的异质 siRNA 混合物的作用。dsRNA 前体消化为异质 siRNA 并不能提高转基因抑制效果。研究重点• 叶面施加 siRNA 可下调拟南芥中常用的转基因。• 甲基化 siRNA 表现出更一致的效果。• 这些发现对于开发植物基因调控方法具有重要意义。
