Significantly low level of small RNA accumulation derived from an encapsidated mycovirus with dsRNA genome
Significantly low level of small RNA accumulation derived from an encapsidated mycovirus with dsRNA genome
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DOI：
10.1016/j.virol.2009.10.008
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发表时间：
2010-01-05
期刊：
影响因子：
3.7
通讯作者：
Namba, Shigetou
中科院分区：
文献类型：
--
作者：
Himeno, Misako;Maejima, Kensaku;Namba, Shigetou
RNA沉默作为一种抗病毒防御的作用在植物和无脊椎动物中已经得到很好的阐明，但在丝状真菌中还没有。我们以前已经确定了完整的基因组序列的稻瘟病菌2型病毒（MoV2），双链RNA病毒，感染稻瘟病菌。在这项研究中，我们从正链和负链MoV 2病毒RNA中检测到了小干扰RNA（siRNA），这表明M.抗真菌功能。MoV2 siRNA的克隆和表征表明，在MoV2中，病毒衍生的siRNA与总小RNA的比率显著低于植物病毒或另一种真菌病毒Cryphonectria hypovirus 1（CHV1）。然而，任何MoV2编码的蛋白质在植物和真菌系统中都没有表现出RNA沉默抑制剂活性。我们的研究表明存在一种新的病毒策略来逃避宿主RNA沉默。(C)2009 Elsevier Inc. All rights reserved.
The role of RNA silencing as an antiviral defence has been well elucidated in plants and invertebrates, but not in filamentous fungi. We have previously determined the complete genome sequence of Magnaporthe oryzae virus 2 (MoV2), a dsRNA virus that infects the rice blast fungus Magnaporthe oryzae. In this study, we detected small interfering RNAs (siRNAs) from both positive- and negative-strand MoV2 viral RNA, suggesting that the RNA silencing machinery in M. oryzae functions against the mycovirus. Cloning and characterisation of MoV2 siRNAs indicated that, in MoV2, the ratio of virus-derived siRNAs to total small RNA is significantly lower than that in either plant viruses or Cryphonectria hypovirus 1 (CHV1), another mycovirus. Nevertheless, any MoV2-encoded proteins did not exhibit RNA silencing suppressor activity in both the plant and fungal systems. Our Study suggests the existence of a novel viral strategy employed to evade host RNA silencing. (C) 2009 Elsevier Inc. All rights reserved.