Feng Qin, Li Yan, Zhao Zhi-Xue, Wang Wen-Ming
Rice Research Institute and Research Center for Crop Disease and Insect Pests, Sichuan Agricultural University at Wenjiang, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China.
Rice (N Y). 2021 Feb 6;14(1):15. doi: 10.1186/s12284-021-00458-z.
Small RNAs (sRNAs) are mainly classified into microRNAs (miRNAs) and small interfering RNAs (siRNAs) according to their origin. miRNAs originate from single-stranded RNA precursors, whereas siRNAs originate from double-stranded RNA precursors that are synthesized by RNA-dependent RNA polymerases. Both of single-stranded and double-stranded RNA precursors are processed into sRNAs by Dicer-like proteins. Then, the sRNAs are loaded into ARGONAUTE proteins, forming RNA-induced silencing complexes (RISCs). The RISCs repress the expression of target genes with sequences complementary to the sRNAs through the cleavage of transcripts, the inhibition of translation or DNA methylation. Here, we summarize the recent progress of sRNA pathway in the interactions of rice with various parasitic organisms, including fungi, viruses, bacteria, as well as insects. Besides, we also discuss the hormone signal in sRNA pathway, and the emerging roles of circular RNAs and long non-coding RNAs in rice immunity. Obviously, small RNA pathway may act as a part of rice innate immunity to coordinate with growth and development.
小RNA（sRNA）主要根据其来源分为微小RNA（miRNA）和小干扰RNA（siRNA）。miRNA来源于单链RNA前体，而siRNA来源于由RNA依赖性RNA聚合酶合成的双链RNA前体。单链和双链RNA前体均由类Dicer蛋白加工成sRNA。然后，sRNA被装载到AGO蛋白中，形成RNA诱导沉默复合体（RISC）。RISC通过切割转录本、抑制翻译或DNA甲基化来抑制与sRNA序列互补的靶基因的表达。在此，我们总结了sRNA途径在水稻与各种寄生生物（包括真菌、病毒、细菌以及昆虫）相互作用中的最新进展。此外，我们还讨论了sRNA途径中的激素信号，以及环状RNA和长链非编码RNA在水稻免疫中的新作用。显然，小RNA途径可能作为水稻先天免疫的一部分，与生长发育相互协调。
