Qin Cheng, Li Bin, Fan Yaya, Zhang Xian, Yu Zhiming, Ryabov Eugene, Zhao Mei, Wang Hui, Shi Nongnong, Zhang Pengcheng, Jackson Stephen, Tör Mahmut, Cheng Qi, Liu Yule, Gallusci Philippe, Hong Yiguo
Research Centre for Plant RNA Signaling, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China (C.Q., B.L., Y.F., X.Z., Z.Y., E.R., M.Z., H.W., N.S., P.C., Y.H.).
Warwick-Hangzhou RNA Signalling Joint Laboratory, School of Life Sciences, University of Warwick, Warwick CV4 7AL, United Kingdom (E.R., S.J., Y.H.).
Plant Physiol. 2017 Jun;174(2):1067-1081. doi: 10.1104/pp.17.00475. Epub 2017 Apr 28.
RNA silencing is an innate antiviral mechanism conserved in organisms across kingdoms. Such a cellular defense involves DICER or DICER-LIKEs (DCLs) that process plant virus RNAs into viral small interfering RNAs (vsiRNAs). Plants encode four that play diverse roles in cell-autonomous intracellular virus-induced RNA silencing (known as VIGS) against viral invasion. VIGS can spread between cells. However, the genetic basis and involvement of vsiRNAs in non-cell-autonomous intercellular VIGS remains poorly understood. Using GFP as a reporter gene together with a suite of RNAi transgenic lines, here we show that despite the well-established activities of in intracellular VIGS and vsiRNA biogenesis, acts to inhibit intercellular VIGS whereas is required (likely along with DCL2-processed/dependent vsiRNAs and their precursor RNAs) for efficient intercellular VIGS trafficking from epidermal to adjacent cells. imposed an epistatic effect on to impede cell-to-cell spread of VIGS. Our results reveal previously unknown functions for and that may form a dual defensive frontline for intra- and intercellular silencing to double-protect cells from virus infection in .
RNA沉默是一种在跨王国的生物体中保守的先天性抗病毒机制。这种细胞防御涉及DICER或类DICER（DCL），它们将植物病毒RNA加工成病毒小干扰RNA（vsiRNA）。植物编码四种在细胞自主的细胞内病毒诱导的RNA沉默（称为VIGS）中对病毒入侵发挥不同作用的（蛋白）。VIGS可以在细胞间传播。然而，vsiRNA在非细胞自主的细胞间VIGS中的遗传基础和作用仍知之甚少。我们使用绿色荧光蛋白（GFP）作为报告基因以及一组RNAi转基因系，表明尽管（某些蛋白）在细胞内VIGS和vsiRNA生物合成中具有既定活性，但（某些蛋白）却起到抑制细胞间VIGS的作用，而（另一些蛋白）（可能连同DCL2加工/依赖的vsiRNA及其前体RNA）对于VIGS从表皮细胞到相邻细胞的有效细胞间运输是必需的。（某些蛋白）对（另一些蛋白）施加上位效应以阻碍VIGS的细胞间传播。我们的结果揭示了（某些蛋白）和（另一些蛋白）以前未知的功能，它们可能形成细胞内和细胞间沉默的双重防御前线，以双重保护细胞免受（植物）病毒感染。
