Discovery and initial analysis of novel viral genomes in the soybean cyst nematode
Discovery and initial analysis of novel viral genomes in the soybean cyst nematode
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DOI：
10.1099/vir.0.030585-0
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发表时间：
2011-08-01
影响因子：
3.8
通讯作者：
Lambert, Kris N.
中科院分区：
文献类型：
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作者：
Bekal, Sadia;Domier, Leslie L.;Lambert, Kris N.
线虫是地球上最丰富的多细胞动物，但人们对其天然病毒病原体知之甚少。迄今为止，仅报道了两种线虫病毒基因组。因此，线虫病毒作为线虫生态学研究中重要的生物因素而被忽视。在这里，我们发现一种植物寄生线虫物种，大豆胞囊线虫 (SCN)，携带四种不同的 RNA 病毒。经过高通量测序和组装后，在 SCN 转录组中发现了线虫病毒基因组。所有四种病毒都具有负义RNA基因组，并且与尼亚病毒和博纳病毒、弹状病毒、布尼亚病毒和细病毒有远缘关系。这些家族的一些成员在昆虫中复制并由昆虫传播，并可能在动植物中引起严重疾病。在卵和 SCN 的第二幼虫阶段都检测到了新的病毒序列，表明这些病毒是垂直传播的。虽然没有证据表明病毒序列整合到线虫基因组中，但我们确实通过定量 PCR 检测到了这些病毒的转录本。这些数据是首次在寄生线虫中发现病毒基因组。这一发现强调需要进一步探索这些多样化和丰富的动物的所有热带类群中的线虫病毒，以确定这些病毒的存在如何影响线虫的适应性、病毒传播的策略和病毒发病机制。
Nematodes are the most abundant multicellular animals on earth, yet little is known about their natural viral pathogens. To date, only two nematode virus genomes have been reported. Consequently, nematode viruses have been overlooked as important biotic factors in the study of nematode ecology. Here, we show that one plant parasitic nematode species, Heterodera glycines, the soybean cyst nematode (SCN), harbours four different RNA viruses. The nematode virus genomes were discovered in the SCN transcriptome after high-throughput sequencing and assembly. All four viruses have negative-sense RNA genomes, and are distantly related to nyaviruses and bornaviruses, rhabdoviruses, bunyaviruses and tenuiviruses. Some members of these families replicate in and are vectored by insects, and can cause significant diseases in animals and plants. The novel viral sequences were detected in both eggs and the second juvenile stage of SCN, suggesting that these viruses are transmitted vertically. While there was no evidence of integration of viral sequences into the nematode genome, we indeed detected transcripts from these viruses by using quantitative PCR. These data are the first finding of virus genomes in parasitic nematodes. This discovery highlights the need for further exploration for nematode viruses in all tropic groups of these diverse and abundant animals, to determine how the presence of these viruses affects the fitness of the nematode, strategies of viral transmission and mechanisms of viral pathogenesis.