Agricultural Biotechnology Center, Plant Biology Institute, H-2101 Gödöllõ, Hungary.
Adv Virus Res. 2009;75:35-71. doi: 10.1016/S0065-3527(09)07502-2. Epub 2010 Jan 13.
RNA silencing is an evolutionarily conserved sequence-specific gene-inactivation system that also functions as an antiviral mechanism in higher plants and insects. To overcome antiviral RNA silencing, viruses express silencing-suppressor proteins which can counteract the host silencing-based antiviral process. After the discovery of virus-encoded silencing suppressors, it was shown that these viral proteins can target one or more key points in the silencing machinery. Here we review recent progress in our understanding of the mechanism and function of antiviral RNA silencing in plants, and on the virus's counterattack by expression of silencing-suppressor proteins. We also discuss emerging evidence that RNA silencing and expression of viral silencing-suppressor proteins are tools forged as a consequence of virus-host coevolution for fine-tuning host-pathogen coexistence.
RNA 沉默是一种进化上保守的序列特异性基因失活系统，在高等植物和昆虫中也作为一种抗病毒机制发挥作用。为了克服抗病毒 RNA 沉默，病毒表达沉默抑制蛋白，这些蛋白可以对抗宿主基于沉默的抗病毒过程。在发现病毒编码的沉默抑制因子后，研究表明这些病毒蛋白可以针对沉默机制中的一个或多个关键点。本文综述了近年来我们对植物抗病毒 RNA 沉默机制和功能的理解的最新进展，以及病毒通过表达沉默抑制蛋白进行反击的情况。我们还讨论了新出现的证据，表明 RNA 沉默和病毒沉默抑制蛋白的表达是作为病毒-宿主共同进化的结果而产生的工具，用于微调宿主-病原体共存。
