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DOI	10.1073/pnas.2102889118
	Cell-free reconstitution reveals the molecular mechanisms for the initiation of secondary siRNA biogenesis in plants
	Sakurai Y.; Baeg K.; Lam A.Y.W.; Shoji K.; Tomari Y.; Iwakawa H.-O.
发表日期	2021
ISSN	0027-8424
卷号	118 期号:31
英文摘要	Secondary small interfering RNA (siRNA) production, triggered by primary small RNA targeting, is critical for proper development and antiviral defense in many organisms. RNA-dependent RNA polymerase (RDR) is a key factor in this pathway. However, how RDR specifically converts the targets of primary small RNAs into double-stranded RNA (dsRNA) intermediates remains unclear. Here, we develop an in vitro system that allows for dissection of the molecular mechanisms underlying the production of trans-acting siRNAs, a class of plant secondary siRNAs that play roles in organ development and stress responses. We find that a combination of the dsRNA-binding protein, SUPPRESSOR OF GENE SILENCING3; the putative nuclear RNA export factor, SILENCING DEFECTIVE5, primary small RNA, and Argonaute is required for physical recruitment of RDR6 to target RNAs. dsRNA synthesis by RDR6 is greatly enhanced by the removal of the poly(A) tail, which can be achieved by the cleavage at a second small RNA-binding site bearing appropriate mismatches. Importantly, when the complementarity of the base pairing at the second target site is too strong, the small RNA-Argonaute complex remains at the cleavage site, thereby blocking the initiation of dsRNA synthesis by RDR6. Our data highlight the light and dark sides of double small RNA targeting in the secondary siRNA biogenesis. © This open access article is distributed under Creative Commons Attribution-NonCommercialNoDerivatives License 4.0 (CC BY-NC-ND).
英文关键词	MicroRNA; Phased siRNA; RNA silencing; Secondary siRNA; Trans-acting siRNA
语种	英语
scopus关键词	plant protein; small interfering RNA; cell free system; cell line; cytology; gene expression regulation; genetics; metabolism; physiology; RNA interference; tobacco; Cell Line; Cell-Free System; Gene Expression Regulation, Plant; Plant Proteins; RNA Interference; RNA, Small Interfering; Tobacco
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/251082
作者单位	Institute for Quantitative Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0032, Japan; Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0032, Japan; Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), Saitama, 332-0012, Japan
推荐引用方式 GB/T 7714	Sakurai Y.,Baeg K.,Lam A.Y.W.,et al. Cell-free reconstitution reveals the molecular mechanisms for the initiation of secondary siRNA biogenesis in plants[J],2021,118(31).
APA	Sakurai Y.,Baeg K.,Lam A.Y.W.,Shoji K.,Tomari Y.,&Iwakawa H.-O..(2021).Cell-free reconstitution reveals the molecular mechanisms for the initiation of secondary siRNA biogenesis in plants.Proceedings of the National Academy of Sciences of the United States of America,118(31).
MLA	Sakurai Y.,et al."Cell-free reconstitution reveals the molecular mechanisms for the initiation of secondary siRNA biogenesis in plants".Proceedings of the National Academy of Sciences of the United States of America 118.31(2021).