Palukaitis P, Roossinck M J
Department of Plant Pathology, Cornell University, Ithaca, NY 14853, USA.
Nat Biotechnol. 1996 Oct;14(10):1264-8. doi: 10.1038/nbt1096-1264.
Plant satellite RNAs generally reduce the level of helper virus accumulation and attenuate the disease symptoms induced by the helper virus that they depend upon for replication and packaging. As such, satellite RNAs could be used as biocontrol agents to reduce the level of disease in field crops, either by the application of a viral vaccine to healthy plants, or by the transgenic expression of satellite RNA in transformed plants. One such virus/satellite RNA system already under use in field tests is cucumber mosaic virus (CMV) and its satellite RNAs. However, in this system, some satellite RNAs also intensify viral disease in particular host plants. We passaged a satellite RNA of CMV with its helper virus to determine whether a satellite RNA that attenuates CMV-induced disease on tobacco plants could mutate to a pathogenic form, which might then be selected. In several experiments involving strains of CMV from each of the two subgroups, the satellite rapidly mutated to a pathogenic form, which was selected. This demonstrates an inherent risk associated with the use of attenuating satellite RNAs as a form of biocontrol of CMV.
植物卫星RNA通常会降低辅助病毒的积累水平，并减轻由它们依赖进行复制和包装的辅助病毒所诱导的病害症状。因此，卫星RNA可作为生物防治剂，通过向健康植物施用病毒疫苗或在转基因植物中进行卫星RNA的转基因表达，来降低大田作物的病害水平。一种已在田间试验中使用的病毒/卫星RNA系统是黄瓜花叶病毒（CMV）及其卫星RNA。然而，在这个系统中，一些卫星RNA也会加剧特定寄主植物中的病毒病害。我们将CMV的一种卫星RNA与其辅助病毒传代培养，以确定一种能减轻烟草植株上CMV诱导病害的卫星RNA是否会突变为致病形式，然后这种致病形式可能会被选择出来。在涉及来自两个亚组中每个亚组的CMV毒株的几个实验中，卫星RNA迅速突变为致病形式，并被选择出来。这证明了将减毒卫星RNA用作CMV生物防治形式所存在的固有风险。
