Department of Plant Pathology and Environmental Microbiology, and Huck Institutes of the Life Sciences, Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA, USA.
J Virol. 2013 Jan;87(2):790-7. doi: 10.1128/JVI.01891-12. Epub 2012 Oct 31.
Cucumber mosaic virus (CMV) comprises numerous isolates with various levels of in-host diversity. Subgroup-distinctive features of the Fny and LS strains provided us with a platform to genetically map the viral control elements for genetic variation in planta. We found that both RNAs 1 and 2 controlled levels of genetic diversity, and further fine mapping revealed that the control elements of mutation frequency reside within the first 596 amino acids (aa) of RNA 1. The 2a/2b overlapping region of the 2a protein also contributed to control of viral genetic variation. Furthermore, the 3' nontranslated region (NTR) of RNA 3 constituted a hot spot of polymorphism, where the majority of fixed mutations found in the population were clustered. The 2b gene of CMV, a viral suppressor of gene silencing, controls the abundance of the fixed mutants in the viral population via a host-dependent mechanism.
黄瓜花叶病毒（CMV）包含具有不同宿主内多样性水平的众多分离株。Fny 和 LS 株的亚组特有特征为我们提供了一个遗传定位病毒控制元件的平台，以研究植物体内遗传变异。我们发现，RNA1 和 RNA2 都控制遗传多样性水平，进一步的精细定位表明突变频率的控制元件位于 RNA1 的前 596 个氨基酸内。2a 蛋白的 2a/2b 重叠区也有助于控制病毒遗传变异。此外，RNA3 的 3'非翻译区（NTR）构成了多态性的热点，群体中发现的大多数固定突变聚集在此。CMV 的 2b 基因是基因沉默的病毒抑制剂，通过一种依赖宿主的机制控制病毒群体中固定突变体的丰度。
