Mutational bias of Turnip Yellow Mosaic Virus in the context of host anti-viral gene silencing.
Mutational bias of Turnip Yellow Mosaic Virus in the context of host anti-viral gene silencing.
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DOI：
10.1016/j.virol.2015.08.024
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发表时间：
2015-12
期刊：
影响因子：
3.7
通讯作者：
Jinmin Ma;D. Pallett;Hui Jiang;Yong Hou;Hui Wang
中科院分区：
文献类型：
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作者：
Jinmin Ma;D. Pallett;Hui Jiang;Yong Hou;Hui Wang
植物Dicer-like（DCL）酶在抗病毒转录后基因沉默（PTGS）期间表现出GC偏好性，提供进化选择压力，导致植物病毒具有GC贫乏的基因组。然而，一些病毒，如芜菁黄花叶病毒（TYMV，属Tymovirus）有GC丰富的基因组，提出了一个问题，是否DCL衍生的选择压力影响这些病毒。在本研究中，我们分析了来自TYMV感染芥菜叶片的病毒衍生的小干扰RNA，表明TYMV群体积累了Au取代GC（GC-Au）的突变偏好，证明了PTGS压力。有趣的是，在高度多态性位点的GC-AU偏差不再观察到。这表明存在一种未知的机制，阻止病毒群体的突变漂移并维持病毒基因组的稳定性，尽管存在宿主PTGS压力。
Plant Dicer-like (DCL) enzymes exhibit a GC-preference during anti-viral post-transcriptional gene silencing (PTGS), delivering an evolutionary selection pressure resulting in plant viruses with GC-poor genomes. However, some viruses,e.g.Turnip Yellow Mosaic Virus(TYMV, genusTymovirus) have GC-rich genomes, raising the question as to whether or not DCL derived selection pressure affects these viruses. In this study we analyzed the virus-derived small interfering RNAs from TYMV-infected leaves ofBrassica junceashowed that the TYMV population accumulated a mutational bias with AU replacing GC (GC–AU), demonstrating PTGS pressure. Interestingly, at the highly polymorphic sites the GC–AU bias was no longer observed. This suggests the presence of an unknown mechanism preventing mutational drift of the viral population and maintaining viral genome stability, despite the host PTGS pressure.