摘要
植物RNA病毒常常伴随有小的卫星RNA。卫星RNA是一类小的非编码RNA,基因组大小为200-1500nt,通常不编码蛋白,完全依赖于辅助病毒来完成复制、包被、移动和传播,且和其辅助病毒的基因组不存在序列同源性。部分卫星RNA可以影响辅助病毒在寄主植物上诱发的症状,多数为减轻,少数会加重寄主症状。传统理论认为卫星RNA是通过与辅助病毒竞争复制酶,减少了辅助病毒的复制,从而减轻了寄主症状。然而,传统理论不能解释卫星RNA在减轻辅助病毒诱导症状的同时,部分辅助病毒复制量不受影响的现象。由此推测,卫星RNA可能存在其它途径来减轻辅助病毒诱导的症状。
RNA沉默(或称为RNAi)是一种广泛存在于真核生物中,由小RNA介导的、以序列特异性的方式抑制或破坏靶标基因表达,在DNA或转录水平上的调控机制。RNA沉默可以调控基因的表达、修饰DNA和特异染色体区域组蛋白的表观遗传、防御转座子和病毒等核酸的入侵。病毒为了成功侵染寄主,也进化了相应的反防卫机制。大部分是通过编码基因沉默抑制子(viral suppressor of RNA silencing, VSR)蛋白结合病毒的siRNA,阻止RNA沉默复合体(RNA-induced silencing complex, RISC)的形成,抑制病毒基因组的降解。
基于RNA沉默具有调控植物正常生长发育和防御病毒的功能、VSR具有干扰RNA沉默反防卫机制、多数卫星RNA在复制过程中伴随着巨量的卫星RNA siRNA产生的三个依据,本文提出了以下假说来解释卫星RNA减轻病毒对寄主植物所诱导的症状。1)病毒通过其产生的VSR干扰寄主植物的miRNA代谢途径,从而致病;2)卫星RNA通过其产生的巨量siRNA捕获并饱和大部分的VSR,减少VSR干扰寄主植物的miRNA代谢途径,减轻病毒对寄主植物诱导的症状。
本文通过对烟草、辅助病毒CMV和Y-卫星RNA(Y-Satellite RNA, Y-Sat)组成的模式系统进行研究,验证了以上假说。模式系统选用CMV亚组Ⅱ的病毒株Q-CMV作为负对照。Y-Sat被选用于本研究,是因为卫星RNA的研究中以对CMV卫星RNA研究最多,而Y-Sat在CMV卫星RNA中具有代表性,可以导致本氏烟和普通烟等的斑驳黄花,方便了对病毒侵染过程的检测。
验证实验分为两个方面,1)应用GUS报告基因监测在有无卫星RNA伴随侵染时P19和2b两种VSR的活性;2)应用miRl68表达量易受VSR诱导的特性,监测在有无卫星RNA伴随侵染时VSR对miR168的影响。验证实验获得了以下几个方面的结果:
1. hpGUS可以有效的沉默GUS,而TBSV的P19和SD-CMV编码的2b两个VSR构件都可以干扰hpGUS介导的GUS沉默。实验采用农杆菌浸润法将GUS+hpGUS、GUS+hpGUS+P19或2b等构件转入本氏烟中进行瞬时表达,比较有无VSR共浸润时GUS蛋白量的变化。并通过GUS染色和GUS的相对酶活性测定分析了P19和2b的活性。实验成功模拟了植物内源的小RNA代谢途径,检验了P19和2b对hpGUS介导的GUS沉默的影响;实验结果与以前报道的VSR可以干扰hpRNA介导RNA沉默的实验结果相吻合。
2. Y-Sat影响了VSR干扰RNA沉默的功能。在野生型本氏烟上进行Q-CMV和Q-CMV+Y-Sat感染实验,然后瞬时表达GUS、hpGUS和P19或2b等构件。在只有Q-CMV感染时,P19和2b都可以干扰hpGUS介导的GUS沉默;在Q-CMV+Y-Sat感染的样品中,P19和2b对GUS的沉默却被削弱了;在只有GUS构件时,存在GUS基因的共抑制现象(另一种RNA沉默形式);在GUS+P19或GUS+2b共浸润的样品中,共抑制现象明显减少,而在有Y-Sat感染时,即使有P19或2b构件的存在,共抑制水平仍然很高。通过对GUS mRNA的Northern印迹分析,GUS mRNA的量与GUS蛋白的量正相关,证实了沉默发生在RNA水平。上述结果证明了Y-Sat能影响VSR干扰RNA沉默的功能,说明VSR对植物内源小RNA介导的沉默途径的影响能被卫星RNA削弱。
3. Y-Sat导致的斑驳黄化对实验体系无明显影响。CMV+Y-Sat共同侵染的本氏烟植株出现了斑驳黄化症状,影响了植物的正常光合作用,也可能对整个实验体系产生干扰。为了排除Y-Sat导致的斑驳黄化对实验体系的影响,实验用CHLI突变体mCHLI转化本氏烟,获得不再出现斑驳黄化植株。应用mCHLI转基因本氏烟F2代,进行了Q-CMV或Q-CMV+Y-Sat的侵染,然后瞬时表达GUS、.hpGUS和P19或2b、GFP等构件。实验结果表明,VSR影响了hpGUS介导的GUS沉默,在有Q-CMV+Y-Sat共侵染的样品中,Y-Sat干扰了VSR的功能。实验结果与在野生型本氏烟中所得结果一致,说明了Y-Sat导致的斑驳黄化对实验体系无明显影响。
4.在Y-Sat感染且有GUS+hpGUS+VSR共浸润的样品中,GUS仍被高度沉默的现象不是由于hpGUS产生更多siRNA所致。在用GUS、hpGUS和P19或2b进行共浸润时,Q-CMV+Y-Sat共同感染比Q-CMV单独感染的样品产生了更高水平的GUS沉默。这种现象的出现有可能是由于Y-Sat干扰了VSR的功能,也有可能是由于hpGUS产生了更多的siRNA,从而介导了更多的GUS沉默。为了排除后一种可能性,实验设计了hpGUS siRNA的Northern印迹检测分析。结果显示,在感染Q-CMV+Y-Sat样品中,hpGUS siRNA的量并没有增加,排除了hpGUS产生更多siRNA介导更多的GUS沉默的可能性。
5.Y-卫星RNA siRNA捕获了VSR,削弱VSR对hpGUS介导的GUS沉默途径的影响。实验应用P19抗体进行RNA-免疫捕获分析,先对植株感染Q-CMV或Q-CMV+Y-Sat处理,再进行GUS、hpGUS、P19共浸润,后采用P19抗体沉淀P19蛋白复合体,并从沉淀复合体中分离RNA,通过Northern印迹分析与P19结合的hpGUS siRNA、Y-Sat siRNA量。结果显示,在Q-CMV感染的样品中,有部分hpGUS siRNA与P19结合;而在Q-CMV+Y-Sat感染的样品中,与P19结合的hpGUS siRNA较少,大部分的P19和Y-Sat siRNA结合在一起。结果说明P19是通过结合hpGUS siRNA来干扰hpGUS介导的GUS沉默;Y-Sat siRNA通过饱和VSR,增加游离的hpGUS siRNA,介导了较高水平的GUS沉默。实验结果进一步表明卫星RNA是通过产生的大量siRNA捕获VSR,从而削弱VSR对寄主小RNA介导的对内源基因调控的干扰。
6. Y-Sat可以削弱CMV编码的2b对miR168的诱导。miRNA在植物生长发育过程中起着至关重要的作用。有报道证实了VSR可以诱导miR168的表达量,miR168负调控AGO1mRNA,影响了植物miRNA代谢途径中关键蛋白AGO1的量。为了证实VSR对植物内源miRNA的影响是病毒致病的主导因素,且卫星RNA可以减少VSR对miRNA代谢的影响,本实验以miR168的表达量为指示,检测了感染CMV亚组Ⅱ(Q-CMV)和CMV亚组Ⅰ(Fny-CMV)及与Y-Sat的本氏烟样品中miR168的表达量。结果显示,Q-CMV和Fny-CMV都可以诱导miRl68的表达量;当有Y-Sat共同感染时,miR168的表达量明显减少,感染植株症状减轻;Fny-CMV可以引起相对于Q-CMV而言更高的miR168累积,感染植株也产生了更严重的症状。结果说明Y-Sat可以削弱CMV编码的2b对miR168的诱导,且miR168的表达量高低与植物发病程度紧密相关。实验用半定量RT-PCR检测CMVRNA4a,发现Y-Sat在削弱2b对miR168诱导的同时,编码2b蛋白CMV RNA4a的量有轻微的减少,导致miR168表达量减少的原因部分可能是由于Y-Sat共同感染时2b量的减少。
7. Y-Sat显著的抑制了P1/HcPro对miR168的诱导。本文应用了由烟草蚀纹病毒(Tobacco etch virus, TEV)编码的VSR P1/HcPro转基因普通烟(N. tabacum)体系对miR168的表达量进行了检测分析。实验结果显示,在P1/HcPro转基因普通烟中,miR168被明显的诱导,同时出现茎基部弯曲生长的表现型;在Q-CMV+Y-Sat共同感染转基因普通烟中,miR168的表达水平显著降低,茎基部弯曲生长的表现型基本消失。实验结果说明,植物病毒VSR通过影响植物内源的miRNA代谢途径而致病,而卫星RNA通过干扰VSR,削弱病毒的致病性,减轻病毒诱导的症状。
以上7个结论,从小RNA的水平验证了植物病毒卫星RNA弱化辅助病毒致病机理的假说,证明了1)病毒通过其产生的VSR干扰寄主植物的miRNA代谢途径,从而致病;2)卫星RNA通过其产生的巨量siRNA捕获并饱和大部分的VSR,减少VSR干扰寄主植物的miRNA代谢途径,减轻病毒对寄主植物诱导的症状。
卫星RNA主要存在于植物病毒,DI RNA主要存在于动物病毒。假说在植物和病毒卫星RNA上面得到了部分验证,作者推断假说还适用于动物和病毒DI RNA。部分动物病毒编码的VSR,也具有结合小RNA的特征,动物病毒的DI RNA,在复制过程可能也会产生大量的siRNA,饱和VSR,干扰VSR的致病性。
Plant RNA viruses are often associated with subviral RNA agents known as satellite RNAs (satRNAs), which are small non-coding RNAs and share little or no sequence homology with their associated virus (helper virus). The genomes of satRNAs are around200-1500nucleotides (nt), which depend on their helper viruses for replication, encapsidation, systemic movement and transmission. The majority of satRNAs attenuate symptoms induced by the helper viruses, while only a few satRNAs have been shown to exacerbate disease phenotypes by inducing their own symptoms in infected host plants. However, how satRNAs attenuate symptoms remains unclear. It has been proposed that satRNAs may reduce helper virus accumulation by competing for RNA replicase or increasing antiviral silencing against the helper virus, thereby reducing symptoms in the host plant. However, symptom reduction by satRNAs is often not associated with a corresponding reduction in helper virus accumulation. This suggests that some other factors or mechanisms may be involved.
RNA silencing is a sequence-specific RNA degradation process induced by double-stranded RNA (dsRNA) or self-complementary hairpin RNA (hpRNA). This dsRNA or hpRNA is processed by Dicer, an RNase Ⅲ-like endoribonuclease, to generate small RNAs (sRNAs), which are loaded onto Argonaute (AGO) proteins to form the RNA-induced silencing complex (RISC). RISC is guided by these sRNAs to bind and degrade cognate mRNAs or other single-stranded RNAs. RNA silencing in plants has been well established as an anti-viral defence mechanism. Viral infection is associated with the accumulation of virus-derived small interfering RNAs (siRNAs), which in turn direct the degradation of viral genome RNAs. To overcome this host defence mechanism, viruses have evolved a counter-defense strategy by encoding suppressors of RNA silencing (VSRs). A predominant mode of action by VSRs is to bind double-stranded sRNAs, thereby preventing the formation of RISC, which is essential for the silencing of viral genomes by the host. VSRs are key symptom determinants of plant viruses, possibly because they interfere with the host sRNA pathways especially the microRNA (miRNA) pathway. miRNAs play critical roles in such processing as cell division, leaf formation and flower development in plants. VSRs affect the expression and function of miRNAs, thereby have the potential to cause developmental abnormalities and hence disease-associated symptoms. A typical example is the enhanced accumulation of miR168caused by viral infection through the function of VSRs. The miR168negatively regulates the expression of AGO1, a key component of RISC. The induction of miR168reduces the expression of AGO1protein, which can subsequently interfere with normal plant development and decrease antiviral RNA silencing, both of which can increase viral disease symptoms.
A recently observed characteristic of satRNAs is that their replication is associated with extremely high amount of satRNA-derived siRNAs (sat-siRNAs). This characteristic, together with the evidence that VSRs interfere with host small RNA function and hence plant development, shows that sat-siRNAs and VSRs may be involved in the symptom attenuation mechanism. In this thesis, a RNA silencing-based hypothesis for satRNA-mediated symptom attenuation was proposed and validated. It is based on that symptom reduction by satRNAs is due to sequestration of VSRs by sat-siRNAs, which minimizes the VSR's interference with host miRNA function.
Firstly, whether satRNA infection would minimize the effect of VSRs on host siRNA-directed gene silencing was tested. Using a β-glucuronidase (GUS) report gene system in conjunction with Agrobacterium-infiltration (Agro-infiltration) assays, the interaction between two VSRs (P19and2b) and Y-satellite RNA (Y-Sat) of Cucumber mosaic virus (CMV) was examined. To facilitate the experiments, a satRNA-free CMV isolate (Q-CMV) and transgenic Nicotiana. benthamiana plants resistant to Y-Sat-induced yellowing symptoms were developed. Results showed that ⅰ) GUS expression was effectively silenced by a hpRNA construct (hpGUS) but this silencing was suppressed by co-Agro-infiltration with P19or2b constructs; ⅱ) Upon Y-Sat infection, strong hpGUS-induced GUS silencing occurred despite the presence of P19 or2b, indicating that the function of the VSRs was interfered with by Y-Sat infection; iii) Agro-infiltrated GUS underwent sense co-suppression, which was inhibited by P19or2b co-infiltration, but upon Y-Sat infection, the co-suppression was enhanced despite the presence of P19or2b, again indicating that the function of the VSRs was interfered with by Y-Sat infection. Taken together, these results indicated that satRNA infection interferes with the function of VSRs and reduces their suppressor effect on small RNA-induced silencing of the host. This is consistent with the hypothesis that satRNAs reduce helper virus-caused symptoms by minimizing the effect of helper virus-encoded VSRs on host miRNA or siRNA-mediated gene regulation.
In order to rule out the possibility if the increased GUS silencing by Y-Sat infection in the presence of VSRs was due to increased amounts of GUS siRNAs, the effect of Y-Sat infection on the accumulation of hpGUS-derived siRNA accumulation was conducted by Northern blot hybridization. Results showed that Y-Sat infection did not affect the processing of hpGUS RNA or the accumulation of hpGUS siRNA, which indicated that the effect of Y-Sat infection on GUS silencing was due to interference with the VSR function.
To demonstrate that satRNA-derived siRNAs indeed bind VSRs and sequester the VSRs from interfering with host sRNA function, RNA-immunoprecipitation was deployed by using P19antibodies to examine the siRNAs associated with P19in the presence or absence of Y-Sat infection. It showed that Y-Sat infection reduced the amount of hpGUS-derived siRNA bound to the P19VSR, and instead, P19was bound with abundant Y-Sat-derived siRNAs. This result indicated that the increased hpGUS-induced silencing by Y-Sat infection in the presence of VSRs was due to saturation of the VSRs by Y-Sat siRNAs, releasing the hpGUS-derived siRNAs available for directing GUS silencing. These results supported the hypothesis that satRNAs reduce the effect of helper virus-encoded VSRs on host sRNA-mediated gene regulation by sequestering the VSRs with Y-Sat siRNAs.
An ultimate demonstration of the hypothesis is to show that the interference of host miRNA or siRNA function is solely or predominantly responsible for helper virus-induced symptoms, and this interference of host sRNA function is diminished upon satRNAs infection. For this purpose, the effect of Y-Sat infection on the accumulation of miR168was examined. miR168is a primary regulator in the host miRNA and siRNA pathways and a key indicator of VSR function. The results showed that infection of N. benthamiana by both subgroup Ⅰ (Fny-CMV) and subgroup Ⅱ (Q-CMV) CMV strains induced miR168accumulation, and this induction was downregulated in the presence of Y-Sat. These results indicated that Y-Sat reduces the helper virus CMV2b-caused induction of miR168. Interestingly, the level of miR168induction was correlated with the severity of CMV-induced symptoms, which implies that the interference of host sRNA pathways by VSRs are indeed responsible for virus-caused symptoms, and Y-Sat-mediated symptom attenuation is indeed due to minimized interference of host sRNA pathways by VSRs.
In addition to CMV-infected N. benthamiana plants, the effect of Y-Sat infection on miR168accumulation in Pl/HcPro (VSR of Tobacco etch virus, TEV) transgenic N. tabacum plants were also investigated. The results showed that Pl/HcPro strongly induced miR168expression, and this induction was largely reversed upon CMV Y-Sat infection. Moreover, the tilted phenotype associated with transgenic Pl/HcPro plants was also largely corrected by CMV Y-Sat infection. These results suggested that satRNA infection generally minimizes the VSR-caused interference of host miRNA and siRNA function in plants, and this diminished effect on host sRNA function accounts for reduced symptoms caused by helper viruses.
In summary, this thesis provides several pieces of experimental evidence to demonstrate an RNA silencing-based hypothesis proposed to answer such a longstanding question as how viral satRNAs attenuate disease symptoms caused by their helper viruses in plants:ⅰ) Agrobacterium infiltration of viral-infected N. benthamiana leaves showed that the Tombusvirus-encoded P19VSR and the CMV-encoded2b VSR both effectively suppressed hpRNA-induced silencing, but this suppression was released upon infection with the CMV Y-Sat; ⅱ) RNA immunoprecipitation showed that, in the presence of Y-Sat, P19was saturated with Y-Sat-derived siRNAs, resulting in reduced amount of hpRNA-derived GUS siRNAs bound to P19; ⅲ) Northern blot hybridization analyses of CMV-infected N. benthamiana plants or P1/HcPro-expressing transgenic N. tabacum plants showed that Y-Sat infection minimized the induction of miR168expression caused either by CMV infection or by overexpression of Pl/HcPro VSR. Taken together, these results support the hypothesis that satRNAs attenuate symptoms by sequestering helper virus-encoded VSRs through abundant satRNA-derived siRNAs, preventing the VSRs from interfering with host siRNA or miRNA-directed gene regulation and hence improving plant development.
引文
1. Agrios GN. Plant pathology. New York and London:Academic press,1969.395-396.
2. Agrios GN. Plant pathology. New York, London, Paris, Sydney:Elsevier Academic Press, 2005.724-756.
3. Hull R. Matthews' Plant Virology 4th edition. Florida,2002.608-627.
4. Brown JF, Ogle HJ. Plant pathogens and plant diseases. Armidale, NSW, Australia:The University of New England Printery,1997.104.
5. Francki RI. Plant virus satellites. Annu Rev Microbiol,1985,39:151-174.
6. Roossinck MJ, Sleat D, Palukaitis P. Satellite RNAs of plant viruses:structures and biological effects. Microbiol Rev,1992,56(2):265-279.
7. Graves MV, Pogany J, Romero J. Defective interfering RNAs and defective viruses associated with multipartite RNA viruses of plants. Semin Virol,1996,7(6):399-408.
8. Simon AE, Roossinck MJ, Havelda Z. Plant virus satellite and defective interfering RNAs: new paradigms for a new century. Annu Rev Phytopathol,2004,42(1):415-437.
9. Wu GS, Kang LY, Tien P. The effect of satellite RNA on cross-protection among Cucumber mosaic-virus strains. Ann Appl Biol,1989,114(3):489-496.
10. Tien P, Wu GS. Satellite RNA for the biocontrol of plant-disease. Advances in Virus Research,1991,39:321-339.
11. Sayama H, Sato T, Kominato M, et al. Field testing of a satellite-containing attenuated strain of Cucumber mosaic-virus for tomato protection in Japan. Phytopathology,1993, 83(4):405-410.
12. Tien P, Zhang XH, Qiu BS, et al. Satellite RNA for the control of plant-diseases caused by Cucumber mosaic virus. Ann Appl Biol,1987,111(1):143-152.
13. Montasser MS, Tousignant ME, Kaper JM. Viral satellite RNAs for the prevention of Cucumber mosaic virus (CMV) disease in field-grown pepper and melon plants. Plant Dis, 1998,82(12):1298-1303.
14. Colhner CW, Howell SH. Role of satellite RNA in the expression of symptoms caused by plant viruses. Annu Rev Phytopathol,1992,30:419-442.
15. White KA, Morris TJ. Defective and defective interfering RNAs of monopartite plus-strand RNA plant viruses. Satellites and Defective Viral RNAs,1999,239:1-17.
16. Murant AF, Mayo MA. Satellites of plant viruses. Annu Rev Phytopathol,1982,20:49-70.
17. Simon AE. Satellite RNA of plant viruses. Plant Mol Biol Rep,1988,6(4):240-252.
18. Hull R. The behavior of salt-labile plant viruses in gradients of cesium sulphate. Virology, 1976,75(1):18-25.
19. Lot H, Kaper JM. Further studies on the RNA component distribution among the nucleoproteins of Cucumber mosaic virus. Virology,1976,74:223-226.
20. Mossop DW, Francki RIB. Association of RNA 3 with aphid transmission of Cucumber mosaic virus. Virology,1977,81(1):177-181.
21. Mossop DW, Francki RIB. Survival of a satellite RNA in vivo and its dependence on Cucumber mosaic virus for replication. Virology,1978,86(2):562-566.
22. Mossop DW, Francki RIB. The stability of satellite viral RNAs in vivo and in vitro. Virology,1979,94(2):243-253.
23. Mossop DW, Francki RIB. Comparative studies on two satellite RNAs of Cucumber mosaic virus. Virology,1979,95(2):395-404.
24. Wang MB, Bian XY, Wu LM, et at On the role of RNA silencing in the pathogenicity and evolution of viroids and viral satellites. Proc Natl Acad Sci USA,2004,101(9):3275-3280.
25. Valverde RA, Dodds JA. Some Properties of Isometric Virus-Particles Which Contain the Satellite RNA of Tobacco Mosaic-Virus. J Gen Virol,1987,68:965-972.
26. Scholthof KB, Jones RW, Jackson AO. Biology and structure of plant satellite viruses activated by icosahedral helper viruses. Curr Top Microbiol Immunol,1999,239:123-143.
27. Jones IM, Reichmann ME. The proteins synthesized in tobacco leaves infected with Tobacco necrosis virus and satellite Tobacco necrosis virus. Virology,1973,52(1):49-56.
28. Huang YW, Baltimore D. Defective viral particles and viral disease processes. Nature,1970, 226:325-327.
29. Huang AS. Defective interfering viruses. Annu Rev Microbiol,1973,27:101-117.
30. Roux L, Simon AE, Holland JJ. Effects of defective interfering viruses on virus replication and pathogenesis in vitro and in vivo. Karl Maramorosch FaM, Aaron JS, eds. Advances in Virus Research. Academic Press,1991.181-211.
31. Russo M, Burgyan J, Martelli GP. Molecular Biology of Tombusviridae. Karl Maramorosch FaM, Aaron JS, eds. Advances in Virus Research. Academic Press,1994.381-428.
32. Hardcastle TJ, Kelly KA, Baulcombe DC. Identifying small interfering RNA loci from high-throughput sequencing data. Bioinformatics,2012,28(4):457-463.
33. Hou WN, Duan CG, Fang RX, et al. Satellite RNA reduces expression of the 2b suppressor protein resulting in the attenuation of symptoms caused by Cucumber mosaic virus infection. Mol Plant Pathol,2011,12(6):595-605.
34. Waterworth HE, Kaper JM, Tousignant ME. CARNA 5, the small Cucumber mosaic virus-dependent replicating RNA, regulates disease expression. Science,1979, 204:845-847.
35. Palukaitis P, Roossinck MJ. Spontaneous change of a benign satellite RNA of Cucumber mosaic virus to a pathogenic variant. Nat Biotech,1996,14(10):1264-1268.
36. Buzayan JM, Gerlach WL, Bruening G, et al. Nucleotide sequence of satellite Tobacco ringspot virus RNA and its relationship to multimeric forms. Virology,1986, 151(2):186-199.
37. Schneider IR. Characteristics of a satellite-like virus of Tobacco ringspot virus. Virology, 1971,45:108-122.
38. Gerlach WL, Buzayan JM, Schneider IR, et al. Satellite Tobacco ringspot virus RNA: Biological activity of DNA clones and their in vitro transcripts. Virology,1986, 151(2):172-185.
39. Murant AF, Mayo MA, Harrison BD, et al. Evidence for two functional RNA species and a 'satellite'RNA in Tomato black ring virus. J Gen Virol,1973,19:275-278.
40. Naidu RA, Collins GB, Ghabrial SA. Symptom-modulating properties of Peanut stunt virus satellite RNA sequence variants. Mol Plant Microbe In,1991,4(3):268-275.
41. Collmer CW, Hadidi A, Kaper JM. Nucleotide sequence of the satellite of Peanut stunt virus reveals structural homologies with viroids and certain nuclear and mitochondrial introns. Proc Natl Acad Sci USA,1985,82(10):3110-3114.
42. Kaper JM, Waterworth HE. Cucumber mosaic virus associated RNA 5:causal agent for tomato necrosis. Science,1977,196(4288):429-431.
43. Davies DL, Clark MF. A satellite-like nucleic-acid of Arabis mosaic virus associated with hop nettlehead disease. Ann ApplBiol,1983,103(3):439-448.
44. Li XH, Simon AE. Symptom intensification on cruciferous hosts by the virulent satellite RNA of Turnip crinkle virus. Phytopathology,1990,80(3):238-242.
45. Zhang FL, Simon AE. Enhanced viral pathogenesis associated with a virulent mutant virus or a virulent satellite RNA correlates with reduced virion accumulation and abundance of free coat protein. Virology,2003,312(1):8-13.
46. Smith NA, Eamens AL, Wang MB. Viral small interfering RNAs target host genes to mediate disease symptoms in plants. PLoS Pathog,2011,7(5):el002022.
47. Shimura H, Pantaleo V, Ishihara T, et al. A Viral Satellite RNA induces yellow symptoms on tobacco by targeting a gene involved in chlorophyll biosynthesis using the RNA silencing machinery. PLoS Pathog,2011,7(5):el002021.
48. Kaper JM, Tousignant ME, Lot H. A low molecular weight replicating RNA associated with a divided genome plant virus:defective or satellite RNA? Biochem Biophys Res Commun, 1976,72(4):1237-1243.
49. Wu G, Kaper JM. Competition of viral and satellite RNAs of Cucumber mosaic virus for replication in vitro by viral RNA-dependent RNA polymerase. Res Virol,1995, 146(1):61-67.
50. Takanami Y. A striking change in symptoms on Cucumber mosaic virus-infected tobacco plants induced by a satellite RNA. Virology,1981,109(1):120-126.
51. Waterworth HE, Kaper JM. Cucumber mosaic virus from Prunus domestica:some diseases incited in herbaceous species in the presence and absence of a small replicating RNA. Acta Phytopathol Hun,1980,15:123-127.
52. Kaper JM. Rapid synthesis of double-stranded Cucumber mosaic virus-associated RNA 5: Mechanism controlling viral pathogenesis? Biochem Bioph Res Co,1982, 105(3):1014-1022.
53. Kaper JM, Tousignant ME. Viral satellites:parasitic nucleic acids capable of modulating disease expression. Endeavour,1984,8(4):194-200.
54. Kaper JM, Tousignant ME. Cucumber mosaic virus-associated RNA 5:1. Role of host plant and helper strain in determining amount of associated RNA 5 with virions. Virology,1977, 80(1):186-195.
55. Gallitelli D, Hull R. Characterization of satellite RNAs associated with Tomato bushy stunt virus and five other definitive Tombusviruses. J Gen Virol,1985,66:1533-1543.
56. Brigneti G, Voinnet O, Li WX, et al. Viral pathogenicity determinants are suppressors of transgene silencing in Nicotiana benthamiana. EMBO J,1998,17(22):6739-6746.
57. Moriones E, Diaz I, Rodriguezcerezo E, et al. Differential interactions among strains of Tomato aspermy virus and satellite RNAs of Cucumber mosaic virus. Virology,1992, 186(2):475-480,
58. Harrison BD, Mayo MA, Baulcombe DC. Virus-resistance in transgenic plants mat express Cucumber mosaic virus satellite RNA. Nature,1987,328(6133):799-802.
59. Chen SC, You SH, Ling MP, et al. Use of seasonal influenza virus titer and respiratory symptom score to estimate effective human contact rates. J Epidemiol,2012,22(4):353-363.
60. Lin NS, Lee YS, Lin BY, et al. The open reading frame of bamboo mosaic potexvirus satellite RNA is not essential for its replication and can be replaced with a bacterial gene. Proc Natl Acad Sci USA,1996,93(7):3138-3142.
61. Waterworth HE, Tousignant ME, Kaper JM. A lethal disease of tomato experimentally induced by RNA-5 associated with Cucumber mosaic virus Isolated from Commelina from El Salvador. Phytopathology,1978,68:561-566.
62. Romano N, Macino G. Quelling-Transient Inactivation of Gene-Expression in Neurospora-Crassa by Transformation with Homologous Sequences. Mol Microbiol,1992, 6(22):3343-3353.
63. Guo S, Kemphues KJ. Par-1, a Gene Required for Establishing Polarity in C-Elegans Embryos, Encodes a Putative Ser/Thr Kinase That Is Asymmetrically Distributed. Cell, 1995,81(4):611-620.
64. Anandalakshmi R, Pruss GJ, Ge X, et al. A viral suppressor of gene silencing in plants. Proc Nail Acad Sci USA,1998,95(22):13079-13084.
65. Kasschau KD, Carrington JC. A counterdefensive strategy of plant viruses:Suppression of posttranscriptional gene silencing. Cell,1998,95(4):461-470.
66. Fire A, Xu SQ, Montgomery MK, et al. Potent and specific genetic interference by double-stranded RNA in Caenorhabditis elegans. Nature,1998,391(6669):806-811.
67. Napoli C, Lemieux C, Jorgensen R. Introduction of a Cbimeric Chalcone Synthase Gene into Petunia Results in Reversible Co-Suppression of Homologous Genes in Trans. Plant Cell,1990,2(4):279-289.
68. Lindbo JA, Silvarosales L, Proebsting WM, et al. Induction of a highly specific antiviral state in transgenic plants - implications for regulation of gene-expression and virus-resistance. Plant Cell,1993,5(12):1749-1759.
69. Waterhouse PM, Graham MW, Wang MB. Virus resistance and gene silencing in plants can be induced by simultaneous expression of sense and antisense RNA. Proc Natl Acad Sci USA,1998,95(23):13959-13964.
70. Zamore PD, Haley B. Ribo-gnome:The big world of small RNAs. Science,2005, 309(5740):1519-1524.
71. Baulcombe DC. RNA silencing in plants. Nature,2004,431 (7006):356-363.
72. Chapman EJ, Carrington JC. Specialization and evolution of endogenous small RNA pathways. Nat Rev Genet,2007,8(11):884-896.
73. Jones-Rhoades MW, Bartel DP, Bartel B. MicroRNAs and their regulatory roles in plants. Annu Rev Plant Biol,2006,57(1):19-53.
74. Vaucheret H. Post-transcriptional small RNA pathways in plants:mechanisms and regulations. GeneDev,2006,20(7):759-771.
75. Meister G, Tuschl T. Mechanisms of gene silencing by double-stranded RNA. Nature,2004, 431(7006):343-349.
76. Eamens A, Wang MB, Smith NA, et al. RNA silencing in plants:Yesterday, Today and Tomorrow. Plant Physiol,2008,147(2):456-468.
77. Zamore PD. RNA interference:listening to the sound of silence. Nat Struct Biol,2001, 8(9):746-750.
78. Schwarz DS, Hutvagner G, Du T, et al. Asymmetry in the assembly of the RNAi enzyme complex. Cell,2003,115(2):199-208.
79. Wang MB, Masuta C, Smith NA, et al. RNA silencing and plant viral diseases. Mol Plant Microbe In,2012,25(10):1275-1285.
80. Manfre AJ, Simon AE. Importance of coat protein and RNA silencing in satellite RNA/virus interactions. Virology,2008,379(1):161-167.
81. Bartel DP. MicroRNAs:genomics, biogenesis, mechanism, and function. Cell,2004, 116(2):281-297.
82. Chen XM. microRNA biogenesis and function in plants. FEBS Lett,2005, 579(26):5923-5931.
83. Brodersen P, Sakvarelidze-Achard L, Bruun-Rasmussen M, et al. Widespread translational inhibition by plant miRNAs and siRNAs. Science,2008,320(5880):1185-1190.
84. Kurihara Y, Watanabe Y. Arabidopsis micro-RNA biogenesis through Dicer-like 1 protein functions. Proc Natl Acad Sci USA,2004,101(34):12753-12758.
85. Reinhart BJ, Weinstein EG, Rhoades MW, et al. MicroRNAs in plants. Gene Dev,2002, 16(13):1616-1626.
86. Lee Y, Jeon K, Lee JT, et al. MicroRNA maturation:stepwise processing and subcellular localization. EMBO J,2002,21(17):4663-4670.
87. Vaucheret H, Vazquez F, Crete P, et al. The action of Argonautel in the miRNA pathway and its regulation by the miRNA pathway are crucial for plant development. Gene Dev, 2004,18(10):1187-1197.
88. Yu L, Yu X, Shen R, et al. HYL1 gene maintains venation and polarity of leaves. Planta, 2005,221(2):231-242.
89. Han MH, Goud S, Song L, et al. The Arabidopsis double-stranded RNA-binding protein HYL1 plays a role in microRNA-mediated gene regulation. Proc Natl Acad Sci USA,2004, 101(4):1093-1098.
90. Fang YD, Spector DL. Identification of nuclear dicing bodies containing proteins for microRNA biogenesis in living Arabidopsis plants. Curr Biol,2007,17(9):818-823.
91. Fujioka Y, Utsumi M, Ohba Y, et al. Location of a possible miRNA processing site in SmD3/SmB nuclear bodies in Arabidopsis. Plant Cell Physiol,2007,48(9):1243-1253.
92. Park W, Li JJ, Song RT, et al. CARPEL FACTORY, a Dicer homolog, and HEN1, a novel protein, act in microRNA metabolism in Arabidopsis thaliana. Curr Biol,2002, 12(17):1484-1495.
93. Chen XM, Liu J, Cheng YL, et al. HEN1 functions pleiotropically in Arabidopsis development and acts in C function in the flower. Development,2002,129(5):1085-1094.
94. Denli AM, Hannon GJ. RNAi:an ever-growing puzzle. Trends Biochem Sci,2003, 28(4):196-201.
95. Hamilton AJ, Baulcombe DC. A species of small antisense RNA in posttranscriptional gene silencing in plants. Science,1999,286(5441):950-952.
96. Moissiard G, Voinnet O. Viral suppression of RNA silencing in plants. Mol Plant Pathol, 2004,5(1):71-82.
97. Voinnet O. Induction and suppression of RNA silencing:insights from viral infections. Nat Rev Genet,2005,6(3):206-220.
98. Moldovan D, Spriggs A, Dennis ES, et al. The hunt for hypoxia responsive natural antisense short interfering RNAs. Plant Signal Behav,2010,5(3):247-251.
99. Jia Y, Lisch DR, Ohtsu K, et al. Loss of RNA-dependent RNA polymerase 2 (RDR2) function causes widespread and unexpected changes in the expression of transposons, genes, and 24-nt small RNAs. PLoS Genet,2009,5(11):e 1000737.
100. Garcia-Ruiz H, Takeda A, Chapman EJ, et al. Arabidopsis RNA-Dependent RNA Polymerases and Dicer-Like Proteins in antiviral defense and small interfering RNA biogenesis during Turnip mosaic virus infection. Plant Cell,2010,22(2):481-496.
101. Ruiz-Ferrer V, Voinnet O. Roles of plant small RNAs in biotic stress responses. Annu Rev Plant Biol,2009,60:485-510.
102. Molnar A, Csorba T, Lakatos L, et al Plant virus-derived small interfering RNAs originate predominantly from highly structured single-stranded viral RNAs. J Virol,2005, 79(12):7812-7818.
103. Szittya G, Moxon S, Pantaleo V, et al. Structural and functional analysis of viral siRNAs. PLoS Pathog,2010,6(4):e 1000838.
104. Pantaleo V, Szittya G, Burgyan J. Molecular bases of viral RNA targeting by viral small interfering RNA-programmed RISC. J Virol,2007,81(8):3797-3806.
105. Donaire L, Wang Y, Gonzalez-Ibeas D, et al. Deep-sequencing of plant viral small RNAs reveals effective and widespread targeting of viral genomes. Virology,2009, 392(2):203-214.
106. Csorba T, Lozsa R, Hutvagner G, et al. Polerovirus protein P0 prevents the assembly of small RNA-containing RISC complexes and leads to degradation of ARGONAUTE1. Plant J,2010,62(3):463-472.
107. Zhang XR, Yuan YR, Pei Y, et al. Cucumber mosaic virus-encoded 2b suppressor inhibits Arabidopsis Argonautel cleavage activity to counter plant defense. Gene Dev,2006, 20(23):3255-3268.
108. Burgyan J, Havelda Z. Viral suppressors of RNA silencing. Trends Plant Sci,2011, 16(5):265-272.
109. Diaz-Pendon JA, Li F, Li WX, et al. Suppression of antiviral silencing by Cucumber mosaic virus 2b protein in Arabidopsis is associated with drastically reduced accumulation of three classes of viral small interfering RNAs. Plant Cell,2007,19(6):2053-2063.
110. Donaire L, Barajas D, Martinez-Garcia B, et al. Structural and genetic requirements for the biogenesis of Tobacco rattle v/rus-derived small interfering RNAs. J Virol,2008, 82(11):5167-5177.
111. Wang XB, Wu QF, Ito T, et al. RNAi-mediated viral immunity requires amplification of virus-derived siRNAs in Arabidopsis thaliana. Proc Natl Acad Sci USA,2010, 107(1):484-489.
112. Fusaro AF, Matthew L, Smith NA, et al. RNA interference-inducing hairpin RNAs in plants act through the viral defence pathway. EMBO Rep,2006,7(11):1168-1175.
113. Qu F, Ye X, Morris TJ. Arabidopsis DRB4, AGO1, AGO7, and RDR6 participate in a DCL4-initiated antiviral RNA silencing pathway negatively regulated by DCL1. Proc Natl Acad Sci USA,2008,105(38):14732-14737.
114. Wang XB, Jovel J, Udomporn P, et al. The 21-nucleotide, but not 22-nucleotide, viral secondary small interfering RNAs direct potent antiviral defense by two cooperative argonautes in Arabidopsis thaliana. Plant Cell,2011,23:1625-1638.
115. Wassenegger M. RNA-directed DNA methylation. Plant Mol Biol,2000,43(2-3):203-220.
116. Fu LY, Liu ZQ, Bai YL. Advances in the RNA-directed DNA methylation in plants. Sheng Wu Gong Cheng Xue Bao,2006,22(6):891-896.
117. Aufsatz W, Mette MF, Van Der Winden J, et al. RNA-directed DNA methylation in Arabidopsis. Proc Natl Acad Sci USA,2002,99:16499-16506.
118. Matzke M, Kanno T, Claxinger L, et al. RNA-mediated chromatin-based silencing in plants. Curr Opin Cell Biol,2009,21(3):367-376.
119. Haag JR, Pikaard CS. Multisubunit RNA polymerases IV and V:purveyors of non-coding RNA for plant gene silencing. Nat Rev Mol Cell Bio,2011,12(8):483-492.
120. Matzke M, Kanno T, Huettel B, et al. RNA-directed DNA methylation and pol IVb in Arabidopsis. Cold Sping Harb Sym 2006,71:449-459.
121. Vaucheret H. RNA polymerase IV and transcriptional silencing. Nat Genet,2005, 37(7):659-660.
122. Zilberman D, Cao X, Jacobsen SE. ARGONAUTE4 control of locus-specific siRNA accumulation and DNA andhistone methylation. Science,2003,299(5607):716-719.
123. Zilberman D, Cao XF, Johansen LK, et al. Role of arabidopsis ARGONAUTE4 in RNA-directed DNA methylation triggered by inverted repeats. Curr Biol,2004, 14(13):1214-1220.
124. Kanno T, Mette MF, Kreil DP, et al. Involvement of putative SNF2 chromatin remodeling protein DRD1 in RNA-directed DNA methylation. Curr Biol,2004,14(9):801-805.
125. Cao XF, Aufsatz W, Zilberman D, et al. Role of the DRM and CMT3 methyltransferases in RNA-directed DNA methylation. Curr Biol,2003,13(24):2212-2217.
126. Voinnet O. RNA silencing:small RNAs as ubiquitous regulators of gene expression. Curr Opin Plant Biol,2002,5(5):444-451.
127. Kramer MF. Stem-loop RT-qPCR for miRNAs. Current Protocols in Molecular Biology. 2011.95.15.10.11-15.10.15.
128. Rhoades MW, Reinhart BJ, Lim LP, et al. Prediction of plant microRNA targets. Cell,2002, 110(4):513-520.
129. Wang MB, Rezaian A, Watson JM, et al. Understanding and exploiting RNA silencing mediated antiviral defense in plants. Floriculture, Ornamental and Plant Biotechnology. 2006.509-522.
130. Xie ZX, Johansen LK, Gustafson AM, et al. Genetic and functional diversification of small RNA pathways in plants. PloS Biology,2004,2(5):642-652.
131. Nykanen A, Haley B, Zamore PD. ATP requirements and small interfering RNA structure in the RNA interference pathway. Cell,2001,107(3):309-321.
132. Elbashir SM, Lendeckel W, Tuschl T. RNA interference is mediated by 21-and 22-nucleotide RNAs. Gene Dev,2001,15(2):188-200.
133. Elbashir SM, Martinez J, Patkaniowska A, et al. Functional anatomy of siRNAs for mediating efficient RNAi in Drosophila melanogaster embryo lysate. EMBO J,2001, 20(23):6877-6888.
134. Khvorova A, Reynolds A, Jayasena SD. Functional siRNAs and miRNAs exhibit strand bias. Cell,2003,115(4):209-216.
135. Bohmert K, Camus I, Bellini C, et al. AGO1 defines a novel locus of Arabidopsis controlling leaf development. EMBO J,1998,17(1):170-180.
136. Carmell MA, Xuan ZY, Zhang MQ, et al. The Argonaute family:tentacles that reach into RNAi, developmental control, stem cell maintenance, and tumorigenesis. Gene Dev,2002, 16(21):2733-2742.
137. Cerutti L, Mian N, Bateman A. Domains in gene silencing and cell differentiation proteins: the novel PAZ domain and redefinition of the Piwi domain. Trends Biochem Sci,2000, 25(10):481-482.
138. Yan KS, Yan S, Farooq A, et al. Structure and conserved RNA binding of the PAZ domain. Nature,2003,426(6965):469-474.
139. Lingel A, Simon B, Izaurralde E, et al. Structure and nucleic-acid binding of the Drosophila Argonaute 2 PAZ domain. Nature,2003,426(6965):465-469.
140. Song JJ, Liu JD, Tolia NH, et al. The crystal structure of the Argonaute2 PAZ domain reveals an RNA binding motif in RNAi effector complexes. Nat Struct Biol,2003, 10(12):1026-1032.
141. Jinek M, Doudna JA. A three-dimensional view of the molecular machinery of RNA interference. Nature,2009,457(7228):405-412.
142. Nowotny M, Gaidamakov SA, Crouch RJ, et al. Crystal structures of RNase H bound to an RNA/DNA hybrid:substrate specificity and metal-dependent catalysis. Cell,2005, 121(7):1005-1016.
143. Chiu YL, Rana TM. RNAi in human cells:Basic structural and functional features of small interfering RNA. Mol Cell,2002,10(3):549-561.
144. Liu JD, Carmell MA, Rivas FV, et al. Argonaute2 is the catalytic engine of mammalian RNAi. Science,2004,305(5689):1437-1441.
145. Mi SJ, Cai T, Hu YG, et al. Sorting of small RNAs into Arabidopsis argonaute complexes is directed by the 5'terminal nucleotide. Cell,2008,133(1):116-127.
146. Montgomery TA, Howell MD, Cuperus JT, et al. Specificity of ARGONAUTE7-miR390 interaction and dual functionality in TAS3 trans-acting siRNA formation. Cell,2008, 133(1):128-141.
147. Williams RW, Rubin GM. ARGONAUTE1 is required for efficient RNA interference in Drosophila embryos. Proc Natl Acad Sci USA,2002,99(10):6889-6894.
148. Sasaki T, Shiohama A, Minoshima S, et al. Identification of eight members of the Argonaute family in the human genome. Genomics,2003,82(3):323-330.
149. Hunter C, Wu G, Sun H, et al. The Arabidopsis heterochronic gene ZIPPY is an ARGONAUTE family member. Dev Biol,2003,259(2):521-522.
150. Hock J, Meister G. The Argonaute protein family. Genome Biol,2008, 9(2):210.211-210.218.
151. Ender C, Meister G. Argonaute proteins at a glance. J Cell Sci,2010,123(11):1819-1823.
152. Ding SW, Voinnet O. Antiviral immunity directed by small RNAs. Cell,2007, 130(3):413-426.
153. Ding SW. RNA-based antiviral immunity. Nat Rev Immunol,2010,10(9):632-644.
154. Voinnet O. RNA silencing as a plant immune system against viruses. Trends Genet,2001, 17(8):449-459.
155. Mlotshwa S, Pruss GJ, Vance V. Small RNAs in viral infection and host defense. Trends Plant Sci,2008,13(7):375-382.
156. Shimura H, Pantaleo V. Viral induction and suppression of RNA silencing in plants. BiochimBiophys Acta,2011,1809(11-12):601-612.
157. Silhavy D, Molnar A, Lucioli A, et al. A viral protein suppresses RNA silencing and binds silencing-generated,21-to 25-nucleotide double-stranded RNAs. EMBO J,2002, 21(12):3070-3080.
158. Goto K, Kobori T, Kosaka Y, et al. Characterization of silencing suppressor 2b of Cucumber mosaic virus based on examination of its small RNA-binding abilities. Plant Cell Physiol,2007,48(7):1050-1060.
159. Chen HY, Yang J, Lin C, et al. Structural basis for RNA-silencing suppression by Tomato aspermy virus protein 2b. EMBO Rep,2008,9(8):754-760.
160. Endres MW, Gregory BD, Gao Z, et al. Two plant viral suppressors of silencing require the ethylene-inducible host transcription factor RAV2 to block RNA silencing. PLoS Pathog, 2010,6(1):e1000729.
161. Merai Z, Kerenyi Z, Kertesz S, et al. Double-stranded RNA binding may be a general plant RNA viral strategy to suppress RNA silencing. J Virol,2006,80(12):5747-5756.
162. Vogler H, Akbergenov R, Shivaprasad PV, et al. Modification of small RNAs associated with suppression of RNA silencing by tobamovirus replicase protein. J Virol,2007, 81(19):10379-10388.
163. Merai Z, Kerenyi Z, Molnar A, et al. Aureusvirus P14 is an efficient RNA silencing suppressor that binds double-stranded RNAs without size specificity. J Virol,2005, 79(11):7217-7226.
164. Bar-Ziv A, Levy Y, Hak H, et al. The Tomato yellow leaf curl virus (TYLCV) V2 protein interacts with the host papain-like cysteine protease CYP1. Plant Signal Behav,2012, 7(8):983-989.
165. Dry IB, Rigden JE, Krake LR, et al. Nucleotide-sequence and genome organization of Tomato leaf curlgeminivirus. J Gen Virol,1993,74:147-151.
166. Jauvion V, Elmayan T, Vaucheret H. The conserved RNA trafficking proteins HPR1 and TEX1 are involved in the production of endogenous and exogenous small interfering RNA in Arabidopsis. Plant Cell,2010,22(8):2697-2709.
167. Zhang J, Dong JY, Xu Y, et al. V2 protein encoded by Tomato yellow leaf curl China virus is an RNA silencing suppressor. Virus Res,2012,163(1):51-58.
168. Voinnet O, Pinto YM, Baulcombe DC. Suppression of gene silencing:A general strategy used by diverse DNA and RNA viruses of plants. Proc Natl Acad Sci USA,1999, 96(24):14147-14152.
169. Yu B, Chapman EJ, Yang Z, et al. Transgenically expressed viral RNA silencing suppressors interfere with microRNA methylation in Arabidopsis. FEBS Lett,2006, 580(13):3117-3120.
170. Bortolamiol D, Pazhouhandeh M, Marrocco K, et al. The Polerovirus Fbox protein P0 targets ARGONAUTE1 to suppress RNA silencing. Curr Biol,2007,17(18):1615-1621.
171. Varallyay, Valoczi A, gyi, et al. Plant virus-mediated induction of miR168 is associated with repression of Argonautel accumulation. EMBO J,2010,29(20):3507-3519.
172. Lozsa R, Csorba T, Lakatos L, et al. Inhibition of 3'modification of small RNAs in virus-infected plants require spatial and temporal co-expression of small RNAs and viral silencing-suppressor proteins. Nucleic Acids Res,2008,36(12):4099-4107.
173. Lakatos L, Csorba T, Pantaleo V, et al. Small RNA binding is a common strategy to suppress RNA silencing by several viral suppressors. EMBO J,2006,25(12):2768-2780.
174. Valli A, Oliveros JC, Molnar A, et al. The specific binding to 21-nt double-stranded RNAs is crucial for the anti-silencing activity of Cucumber vein yellowing virus Plb and perturbs endogenous small RNA populations. RNA,2011,17(6):1148-1158.
175. Hamera S, Song XG, Su L, et al. Cucumber mosaic virus suppressor 2b binds to AGO4-related small RNAs and impairs AGO4 activities. Plant J,2012:104-115.
176. Scholthof HB, Scholthof KBG, Jackson AO. Identification of Tomato bushy stunt virus host-specific symptom determinants by expression of individual genes from a Potato-virus-Xvector. Plant Cell,1995,7(8):1157-1172.
177. Qiu WP, Park JW, Scholthof HB. Tombusvirus pl9-mediated suppression of virus-induced gene silencing is controlled by genetic and dosage features that influence pathogenicity. Mol Plant Microbe In,2002,15(3):269-280.
178. Qu F, Morris TJ. Efficient infection of Nicotiana benthamiana by Tomato bushy stunt virus is facilitated by the Coat Protein and maintained by pi9 through suppression of gene silencing. Mol Plant Microbe In,2002,15(3):193-202.
179. Vargason JM, Szittya G, Burgyan J, et al. Size selective recognition of siRNA by an RNA silencing suppressor. Cell,2003,115(7):779-811.
180. Baulcombe DC, Molnar A. Crystal structure of pl9-a universal suppressor of RNA silencing. Trends Biochem Sci,2004,29(6):279-281.
181. Gonzalez I, Rakitina D, Semashko M, et al. RNA binding is more critical to the suppression of silencing function of Cucumber mosaic virus 2b protein than nuclear localization. RNA, 2012,18(4):771-782.
182. Mayers CN, Palukaitis P, Carr JP. Subcellular distribution analysis of the Cucumber mosaic virus 2b protein. J Gen Virol,2000,81(Pt 1):219-226.
183. Lucy AP, Guo HS, Li WX, et al. Suppression of post-transcriptional gene silencing by a plant viral protein localized in the nucleus. EMBO J,2000,19(7):1672-1680.
184. Jin HL, Zhu JK. A viral suppressor protein inhibits host RNA silencing by hooking up with Argonautes. Gene Dev,2010,24(9):853-856.
185. Thomas CL, Leh V, Lederer C, et al. Turnip crinkle virus coat protein mediates suppression of RNA silencing in Nicotiana benthamiana. Virology,2003,306(1):33-41.
186. Azevedo J, Garcia D, Pontier D, et al. Argonaute quenching and global changes in Dicer homeostasis caused by a pathogen-encoded GW repeat protein. Gene Dev,2010, 24(9):904-915.
187. Reed JC, Kasschau KD, Prokhnevsky Al, et al. Suppressor of RNA silencing encoded by Beet yellows virus. Virology,2003,306(2):203-209.
188. Peremyslov W, Hagiwara Y, Dolja W. Genes required for replication of the 15.5-kilobase RNA genome of a plant closterovirus. J Virol,1998,72(7):5870-5876.
189. Chapman EJ, Prokhnevsky AI, Gopinath K, et al. Viral RNA silencing suppressors inhibit the microRNApathway at an intermediate step. Gene Dev,2004,18(10):1179-1186.
190. Lu R, Folimonov A, Shintaku M, et al. Three distinct suppressors of RNA silencing encoded by a 20-kb viral RNA genome. Proc Natl Acad Sci USA,2004, 101(44):15742-15747.
191. Pappu SS, Febres VJ, Pappu HR, et al. Characterization of the 3'proximal gene of the Citrus tristeza closterovirus genome. Virus Res,1997,47(1):51-57.
192. Ghorbel R, Lopez C, Fagoaga C, et al. Transgenic citrus plants expressing the citrus tristeza virus p23 protein exhibit viral-like symptoms. Mol Plant Pathol,2001,2(1):27-36.
193. Fagoaga C, Lopez C, Moreno P, et al. Viral-like symptoms induced by the ectopic expression of the p23 gene of Citrus tristeza virus are citrus specific and do not correlate with the pathogenicity of the virus strain. Mol Plant Microbe In,2005,18(5):435-445.
194. Fagoaga C, Lopez C, De Mendoza AH, et al. Post-transcriptional gene silencing of the p23 silencing suppressor of Citrus tristeza virus confers resistance to the virus in transgenic Mexican lime. Plant Mol Biol,2006,60(2):153-165.
195. Fagoaga C, Pensabene-Bellavia G, Moreno P, et al. Ectopic expression of the p23 silencing suppressor of Citrus tristeza virus differentially modifies viral accumulation and tropism in two transgenic woody hosts. Mol Plant Pathol,2011,12(9):898-910.
196. Liu L, Grainger J, Canizares MC, et al. Cowpea mosaic virus RNA-1 acts as an amplicon whose effects can be counteracted by a RNA-2-encoded suppressor of silencing. Virology, 2004,323(1):37-48.
197. Cuellar WJ, Cruzado RK, Fuentes S, et al. Sequence characterization of a Peruvian isolate of Sweet potato chlorotic stunt virus:Further variability and a model for p22 acquisition. Virus Res,2011,157(1):111-115.
198. Cuellar WJ, Kreuze JF, Rajamaki ML, et al. Elimination of antiviral defense by viral RNase Ⅲ. Proc Natl Acad Sci USA,2009,106(25):10354-10358.
199. Lewsey M, Surette M, Robertson FC, et al. The role of the Cucumber mosaic virus 2b protein in viral movement and symptom induction. Mol Plant Microbe In,2009, 22(6):642-654.
200. Guo HS, Ding SW. A viral protein inhibits the long range signaling activity of the gene silencing signal. EMBO J,2002,21(3):398-407.
201. Yelina NE, Savenkov El, Solovyev AG, et al. Long-distance movement, virulence, and RNA silencing suppression controlled by a single protein in hordei-and potyviruses: Complementary functions between virus families. J Virol,2002,76(24):12981-12991.
202. Bragg JN, Jackson AO. The C-terminal region of the Barley stripe mosaic virus yb protein participates in homologous interactions and is required for suppression of RNA silencing. Mol Pant Pathol,2004,5(5):465-481.
203. Bragg JN, Lawrence DM, Jackson AO. The N-terminal 85 amino acids of the Barley stripe mosaic virus yb pathogenesis protein contain three Zinc-binding motifs. J Virol,2004, 78(14):7379-7391.
204. Dunoyer P, Pfeffer S, Fritsch C, et al. Identification, subcellular localization and some properties of a cysteine-rich suppressor of gene silencing encoded by Peanut clump virus. Plant J,2002,29(5):555-567.
205. Pfeffer S, Dunoyer P, Heim F, et al. P0 of Beet western yellows virus is a suppressor of posttranscriptional gene silencing. J Virol,2002,76(13):6815-6824.
206. Pazhouhandeh M, Dieterle M, Marrocco K, et al. F-box-like domain in the polerovirus protein P0 is required for silencing suppressor function. Proc Natl Acad Sci USA,2006, 103(6):1994-1999.
207. Voinnet O, Lederer C, Baulcombe DC. A viral movement protein prevents spread of the gene silencing signal in Nicotiana benthamiana. Cell,2000,103(1):157-167.
208. Kalinina NO, Rakitina DV, Solovyev AG, et al. RNA helicase activity of the plant virus movement proteins encoded by the first gene of the triple gene block. Virology,2002, 296(2):321-329.
209. Morozov SY, Solovyev AG. Triple gene block:modular design of a multifunctional machine for plant virus movement. J Gen Virol,2003,84:1351-1366.
210. Morozov SY, Solovyev AG, Kalinina NO, et al. Evidence for two nonoverlapping functional domains in the Potato virus X 25K movement protein. Virology,1999, 260(1):55-63.
211. Chiu MH, Chen IH, Baulcombe DC, et al. The silencing suppressor P25 of Potato virus X interacts with Argonautel and mediates its degradation through the proteasome pathway. Mol Plant Pathol,2010, 11(5):641-649.
212. Kubota K, Tsuda S, Tamai A, et al. Tomato mosaic virus replication protein suppresses virus-targeted posttranscriptional gene silencing. J Virol,2003,77(20):11016-11026.
213. Citovsky V, Knorr D, Schuster G, et al. The P30 movement protein of Tobacco mosaic virus is a single-strand nucleic acid binding protein. Cell,1990,60(4):637-647.
214. Guilley H, Bortolamiol D, Jonard G, et al. Rapid screening of RNA silencing suppressors by using a recombinant virus derived from Beet necrotic yellow vein virus. J Gen Virol, 2009,90:2536-2541.
215. Vogler H, Kwon MO, Dang V, et al. Tobacco mosaic virus movement protein enhances the spread of RNA silencing. PLoS Pathog,2008,4(4):e1000038.
216. Csorba T, Bovi A, Dalmay T, et al. The p122 subunit of Tobacco mosaic virus replicase is a potent silencing suppressor and compromises both small Interfering RNA- and microRNA-mediated pathways. J Virol,2007,81(21):11768-11780.
217. Takeda A, Tsukuda M, Mizumoto H, et al. A plant RNA virus suppresses RNA silencing through viral RNA replication. EMBO J,2005,24(17).:3147-3157.
218. Chen J, Li WX, Xie DX, et al. Viral virulence protein suppresses RNA silencing-mediated defense but upregulates the role of microRNA in host gene expression. Plant Cell,2004, 16(5):1302-1313.
219. Baumberger N, Tsai CH, Lie M, et al. The polerovirus silencing suppressor P0 targets ARGONAUTE proteins for degradation. Curr Biol,2007,17(18):1609-1614.
220. Bucher E, Sijen T, De Haan P, et al. Negative-strand tospoviruses and tenuiviruses carry a gene for a suppressor of gene silencing at analogous genomic positions. J Virol,2003, 77(2):1329-1336.
221. Schnettler E, De Vries W, Hemmes H, et al. The NS3 protein of Rice hoja blanca virus complements the RNAi suppressor function of HIV-1 Tat. EMBO Rep,2009, 10(3):258-263.
222. Wezel RV, Dong XL, Liu HT, et al. Mutation of three cysteine residues in Tomato yellow leaf curl virus-China C2 protein causes dysfunction in pathogenesis and posttranscriptional gene-silencing suppression. Mol Plant Microbe In,2002,15(3):203-208.
223. Wang H, Buckley KJ, Yang XJ, et al. Adenosine kinase inhibition and suppression of RNA silencing by geminivirus AL2 and L2 proteins. J Virol,2005,79(12):7410-7418.
224. Yang X, Baliji S, Buchmann RC, et al. Functional modulation of the geminivirus AL2 transcription factor and silencing suppressor by self-interaction. J Virol,2007, 81(21):11972-11981.
225. Geri C, Cecchini E, Giannakou ME, et al. Altered patterns of gene expression in Arabidopsis elicited by Cauliflower mosaic virus (CaMV) infection and by a CaMV gene VI transgene. Mol Plant Microbe In,1999,12(5):377-384.
226. Love AJ, Laird J, Holt J, et al. Cauliflower mosaic virus protein P6 is a suppressor of RNA silencing. J Gen Virol,2007,88:3439-3444.
227. Urcuqui-Inchima S, Maia IG, Arruda P, et al. Deletion mapping of the potyviral helper component-proteinase reveals two regions involved in RNA binding. Virology,2000, 268(1):104-111.
228. Plisson C, Drucker M, Blanc S, et al. Structural characterization of HC-Pro, a plant virus multifunctional protein. J Biol Chem,2003,278(26):23753-23761.
229. Ruiz-Ferrer V, Boskovic J, Alfonso C, et al. Structural analysis of tobacco etch potyvirus HC-pro oligomers involved in aphid transmission. J Virol,2005,79(6):3758-3765.
230. Shiboleth YM, Haronsky E, Leibman D, et al. The conserved FRNK box in HC-Pro, a plant viral suppressor of gene silencing, is required for small RNA binding and mediates symptom development. J Virol,2007,81(23):13135-13148.
231. Aliyari R, Wu QF, Li HW, et al. Mechanism of induction and suppression of antiviral immunity directed by virus-derived small RNAs in Drosophila. Cell Host Microbe,2008, 4(1934-6069 (Electronic)):387-397.
232. Gonzalez I, Martinez L, Rakitina DV, et al. Cucumber mosaic virus 2b protein subcellular targets and interactions:their significance to RNA silencing suppressor activity. Mol Plant Microbe In,2010,23:294-303.
233. Duan CG, Fang YY, Zhou BJ, et al. Suppression of Arabidopsis ARGONAUTE1-mediated slicing, transgene-induced RNA silencing, and DNA methylation by distinct domains of the Cucumber mosaic virus 2b protein. Plant Cell,2012,24(1):259-274.
234. Mayo MA, Zieglergraff V. Molecular biology of luteoviruses. Advances in Virus Research, 1996,46:413-460.
235. Giner A, Lakatos L, Garcia-Chapa M, et al. Viral protein inhibits RISC activity by Argonaute binding through conserved WG/GW motifs. PLoS Pathog,2010,6(7):e1000996.
236. Haas G, Azevedo J, Moissiard G, et al. Nuclear import of CaMV P6 is required for infection and suppression of the RNA silencing factor DRB4. EMBO J,2008,27(15):2102-2112.
237. Deleris A, Gallego-Bartolome J, Bao JS, et al. Hierarchical action and inhibition of plant Dicer-like proteins in antiviral defense. Science,2006,313(5783):68-71.
238. Bouche N, Lauressergues D, Gasciolli V, et al. An antagonistic function for Arabidopsis DCL2 in development and a new function for DCL4 in generating viral siRNAs. EMBO J, 2006,25(14):3347-3356.
239. Ebhardt HA, Thi EP, Wang MB, et al. Extensive 3'modification of plant small RNAs is modulated by helper component-proteinase expression. Proc Natl Acad Sci USA,2005, 102(38):13398-13403.
240. Hutvagner G, Simard MJ. Argonaute proteins:key players in RNA silencing. Nat Rev Mol Cell Bio,2008,9(1):22-32.
241. Zhu SF, Gao F, Cao XS, et al. The Rice dwarf virus P2 protein interacts with ent-kaurene oxidases in vivo, leading to reduced biosynthesis of gibberellins and rice dwarf symptoms. Plant Physiol,2005,139(4):1935-1945.
242. Inaba J, Kim BM, Shimura H, et al. Virus-induced necrosis is a consequence of direct protein-protein interaction between a viral RNA-silencing suppressor and a host catalase. Plant Physiol,2011,156(4):2026-2036.
243. Kasschau KD, Xie Z, Allen E, et al. P1/HC-Pro, a viral suppressor of RNA silencing, interferes with Arabidopsis development and miRNA function. Dev Cell,2003, 4(2):205-217.
244. Diermann N, Matousek J, Junge M, et al. Characterization of plant miRNAs and small RNAs derived from Potato spindle tuber viroid (PSTVd) in infected tomato. Biol Chem, 2010,391(12):1379-1390.
245. Gomez G, Martinez G, Pallas V. Viroid-induced symptoms in Nicotiana benthamiana plants are dependent on RDR6 activity. Plant Physiol,2008,148(1):414-423.
246. Moissiard G, Voinnet O. RNA silencing of host transcripts by cauliflower mosaic virus requires coordinated action of the four Arabidopsis Dicer-like proteins. Proc Natl Acad Sci USA,2006,103(51):19593-19598.
247. Ding SW, Shi BJ, Li WX, et al. An interspecies hybrid RNA virus is significantly more virulent than either parental virus. Proc Natl Acad Sci USA,1996,93(15):7470-7474.
248. Zhang BH, Wang QL, Pan XP. MicroRNAs and their regulatory roles in animals and plants. J Cell Physiol,2007,210(2):279-289.
249. Chellappan P, Vanitharani R, Fauquet CM. MicroRNA-binding viral protein interferes with Arabidopsis development. Proc Natl Acad Sci USA,2005,102(29):10381-10386.
250. Du P, Wu JG, Zhang JY, et al. Viral infection induces expression of novel phased microRNAs from conserved cellular microRNA precursors. PLoS Pathog,2011, 7(8):el002176.
251. Senda M, Masuta C, Ohnishi S, et al. Patterning of virus-infected Glycine max seed coat is associated with suppression of endogenous silencing of chalcone synthase genes. Plant Cell, 2004,16(4):807-818.
252. Edwardson JR, Christie RG. CRC handbook of viruses infecting legumes. Florida, Ameirica: CRC press,1991.294-303.
253. Peden KW, Symons RH. Cucumber mosaic virus contains a functionally divided genome. Virology,1973,53(2):487-492.
254. Harrison BD, Finch JT, Gibbs AJ, et al. Sixteen groups of plant viruses. Virology,1971, 45(2):356-363.
255. Palukaitis P, Roossinck MJ, Dietzgen RG, et al. Cucumber mosaic Virus. Advances in Virus Research. California:Acdemic press,1992.41.281-348.
256. Palukaitis P, Garcia-Arenal F. Cucumber mosaic virus. In. Descriptions of Plant Viruses, 2003.
257. Hayes RJ, Buck KW. Complete replication of a eukaryotic virus RNA in vitro by a purified RNA-dependent RNA polymerase. Cell,1990,63(2):363-368.
258. Ding B, Li Q, Nguyen L, et al. Cucumber mosaic virus 3a protein potentiates cell-to-cell trafficking of CMV RNA in tobacco plants. Virology,1995,207(2):345-453.
259. Li Q, Ryu KH, Palukaitis P. Cucumber mosaic virus-plant interactions:Identification of 3a protein sequences affecting infectivity, cell-to-cell movement, and long-distance movement. Mol Plant Microbe In,2001,14(3):378-385.
260. Ding SW, Anderson BJ, Haase HR, et al. New overlapping gene encoded by the Cucumber mosaic virus genome. Virology,1994,198(2):593-601.
261. Schwinghamer MW, Symons RH. Fractionation of Cucumber mosaic virus RNA and its translation in a wheat embryo cell-free system. Virology,1975,63(1):252-262.
262. Lewsey M, Robertson FC, Canto T, et al. Selective targeting of miRNA-regulated plant development by a viral counter-silencing protein. Plant J,2007,50(2):240-252.
263. Mlotshwa S, Voinnet O, Mette MF, et al. RNA silencing and the mobile silencing signal. Plant Cell,2002,14:S289-S301.
264. Ding SW, Li WX, Symons RH. A novel naturally occurring hybrid gene encoded by a plant RNA virus facilitates long distance virus movement. EMBO J,1995,14(23):5762-5772.
265. Ji LH, Ding SW. The suppressor of transgene RNA silencing encoded by Cucumber mosaic virus interferes with salicylic acid-mediated virus resistance. Mol Plant Microbe In,2001, 14(6):715-724.
266. Shi B-J, Palukaitis P, Symons RH. Differential virulence by strains of Cucumber mosaic virus is mediated by the 2b gene. Mol Plant Microbe In,2002,15(9):947-955.
267. Edward MC, Gonsalves D. Grouping of seven biologically defined isolates of Cucumber mosaic virus by peptide mapping. Phytopathology,1983,73:1117-1120.
268. Rizos H, Gunn LV, Pares RD, et al. Differentiation of Cucumber mosaic virus isolates using the Polymerase Chain-Reaction. J Gen Virol,1992,73:2099-2103.
269. Wylie S, Wilson CR, Jones RaC, et al. A polymerase chain-reaction assay for Cucumber mosaic-virus in lupin seeds. Aust J Aar Rer 1993,44(1):41-51.
270. Roossinck MJ, Zhang L, Hellwald KH. Rearrangements in the 5'nontranslated region and phylogenetic analyses of Cucumber mosaic virus RNA 3 indicate radial evolution of three subgroups. J Virol,1999,73(8):6752-6758.
271. Fang RX, Ye J, Qua J, et al. A critical domain of the Cucumber mosaic virus 2b protein for RNA silencing suppressor activity. FEBS Lett,2009,583(1):101-106.
272. Avila-Rincon MJ, Collmer CW, Kaper JM. In vitro translation of cucumoviral satellites I. Purification and nucleotide sequence of Cucumber mosaic virus-associated RNA 5 from Cucumber mosaic virus strain S. Virology,1986,152(2):446-454.
273. Garcia-Arenal F, Zaitlin M, Palukaitis P. Nucleotide sequence analysis of six satellite RNAs of Cucumber mosaic virus:Primary sequence and secondary structure alterations do not correlate with differences in pathogenicity. Virology,1987,158(2):339-347.
274. Kaper JM, Tousignant ME, Steen MT. Cucumber mosaic virus-associated RNA 5 XI. Comparison of 14 CARNA 5 variants relates ability to induce tomato necrosis to a conserved nucleotide sequence. Virology,1988,163(2):284-292.
275. Choi SK, Jeon YW, Yoon JY, et al. Characterisation of a satellite RNA of Cucumber mosaic virus that induces chlorosis in Capsicum annuum. Virus Genes,2011, 43(1):111-119.
276. Garcia-Arenal F, Palukaitis P. Sturcture and functianl relationships of satellite RNAs of Cucumber mosaic virus. Vogt PK, Jackson AO, eds. Curr Top Microbiol Immunol. Berlin Heidelberg, Germany:Springer-Verlag,1999.239.37-63.
277. Masuta C, Takanami Y. Determination of sequence and structural requirements for pathogenicity of a Cucumber mosaic virus satellite RNA (Y-satRNA). Plant Cell,1989, 1(12):1165-1173.
278. Fritsch C, Mayo MA. Satellites of plant viruses. Plant Viruses. CRC Press,1988.1, structure and repication.289-321.
279. Goodin MM, Zaitlin D, Naidu RA, et al. Nicotiana benthamiana:Its history and future as a model for plant-pathogen interactions. Mol Plant Microbe In,2008,21(8):1015-1026.
280. Ueki S, Magori S, Lacroix B, et al. Transient Gene Expression in Epidermal Cells of Plant Leaves by Biolistic DNA Delivery. Sudowe S, Reske-Kunz AB, eds. Biolistic DNA Delivery. Humana Press, Methods in Molecular Biology; 2013.940.17-26.
281. Ellis JG, Llewellyn DJ, Dennis ES, et al. Maize Adh-1 promoter sequences control anaerobic regulation-addition of upstream promoter elements from constitutive genes is necessary for expression in tobacco. EMBO J,1987,6(1):11-16.
282. Scholthof HB, Scholthof K-BG, Kikkert M, et al. Tomato bushy stunt virus spread is regulated by two nested genes that function in cell-to-cell movement and host-dependent systemic invasion. Virology,1995,213(2):425-438.
283. Omarov R, Sparks K, Smith L, et al. Biological relevance of a stable biochemical interaction between the Tombusvirus-encoded P19 and short interfering RNAs. J Virol, 2006,80(6):3000-3008.
284. Scholthof HB. Timeline-The Tombusvirus-encoded P19:from irrelevance to elegance. Nat Rev Microbiol,2006,4(5):405-411.
285. Marathe R, Smith TH, Anandalakshmi R, et al. Plant viral suppressors of post-transcriptional silencing do not suppress transcriptional silencing. Plant J,2000, 22(1):51-59.
286. Soitamo AJ, Jada B, Lehto K. HC-Pro silencing suppressor significantly alters the gene expression profile in tobacco leaves and flowers. BMC Plant Biol,2011,11(1):1-16.
287. Havelda Z, Hornyik C, Valoczi A, et al. Defective interfering RNA hinders the activity of a Tombusvirus-encoded posttranscriptional gene silencing suppressor. J Virol,2005, 79(1):450-457.
288. Colosi JC, Schaal BA. Tissue grinding with ball bearings and vortex mixer for DNA extraction. Nucleic Acids Res,1993,21(4):1051-1052.
289. Sharma RC, Schimke RT. Preparation of electrocompetent E. coli using salt-free growth medium. Biotechniques,1996,20(l):42-44.
290. Wood CC, Petrie JR, Shrestha P, et al. A leaf-based assay using interchangeable design principles to rapidly assemble multistep recombinant pathways. Plant Biotechnol J,2009, 7(9):914-924.
291. Ishikawa A. The Arabidopsis G-Protein beta-subunit is required for defense response against Agrobacterium tumefaciens. Biosci Biotech Bioch 2009,73(1):47-52.
292. Ohta S, Mita S, Hattori T, et al. Construction and expression in Tobacco of a P-Glucuronidase (GUS) reporter gene dontaining an intron within the coding sequence. Plant Cell Physiol,1990,31(6):805-813.
293. Ditta G, Stanfield S, Corbin D, et al. Broad host range DNA cloning system for gram-eegative bacteria-construction of a gene bank of Rhizobium-meliloti. Proc Natl Acad Sci USA,1980,77(12):7347-7351.
294. Francki RIB, Randies JW, Chambers TC, et al. Some Properties of Purified Cucumber Mosaic Virus (Q Strain). Virology,1966,28(4):729-741.
295. Ding SW, Rathjen JP, Li WX, et al. Efficient infection from cDNA clones of Cucumber mosaic Cucumovirus RNAs in a new plasmid vector. J Gen Virol,1995,76:459-464.
296. Liu L, Lomonossoff GP. Agroinfection as a rapid method for propagating Cowpea mosaic vims-based constructs. J Virol Methods,2002,105(2):343-348.
297. Jefferson RA, Kavanagh TA, Bevan MW. GUS fusions:beta-glucuronidase as a sensitive and versatile gene fusion marker in higher-plants. EMBO J,1987,6(13):3901-3907.
298. Chen S, Helliwell CA, Wu LM, et al. A novel T-DNA vector design for selection of transgenic lines with simple transgene integration and stable transgene expression. Funct Plant Biol,2005,32(8):671-681.
299. Sambrook J, Fritisch EF, Mantatis T. Molecular cloning:Alaboratory manual (2nd edition). New York:Cold spring harbor laboratory press,1989.7.1-7.25.
300. Wang MB, Wesley SV, Finnegan EJ, et al. Replicating satellite RNA induces sequence-specific DNA methylation and truncated transcripts in plants. RNA,2001, 7(1):16-28.
301. Jones L, Keining T, Eamens A, et al. Virus-induced gene silencing of Argonaute genes in Nicotiana benthamiana demonstrates that extensive systemic silencing requires Argonautel-like and Argonaute4-like genes. Plant Physiol,2006,141(2):598-606.
302. Eamens AL, Agius C, Smith NA, et al. Efficient silencing of endogenous microRNAs using artificial microRNAs in Arabidopsis thaliana. Mol Plant,2011,4(1):157-170.
303. Cazzonelli CI, Velten J. An in vivo, luciferase-based, Agrobacterium-infiltration assay system:implications for post-transcriptional gene silencing. Planta,2006,224(3):582-597.
304. Wang MB, Waterhouse PM. High-efficiency silencing of a beta-glucuronidase gene in rice is correlated with repetitive transgene structure but is independent of DNA methylation. Plant Mol Biol,2000,43(1):67-82.
305. Ebhardt HA, Unrau PJ. Characterizing multiple exogenous and endogenous small RNA populations in parallel with subfemtomolar sensitivity using a streptavidin gel-shift assay. RNA,2009,15(4):724-731.
306. Jovel J, Schneemann A. Molecular characterization of Drosophila cells persistently infected*-with Flock House virus. Virology,2011,419(1):43-53.