利用小RNA深度测序技术检测灰飞虱病毒种类

灰飞虱是一种重要农业害虫,作为病毒介体,可以传播多种植物病毒引起水稻、小麦和玉米等粮食作物病毒病害。目前对于灰飞虱体内昆虫病毒种类尚缺乏系统认识,难以开展利用昆虫病毒防治灰飞虱相关研究工作。为挖掘灰飞虱体内昆虫病毒资源,本文通过小RNA深度测序技术对灰飞虱所携带的病毒种类进行分析鉴定。结果显示,测序数据比对得到13种病毒,涉及8个病毒科和2种未分类病毒。除占据优势的水稻条纹病毒外,其余均为专性寄生的昆虫病毒,包括5种正链RNA病毒、2种单链DNA病毒和5种双链DNA病毒。在这些病毒中,发现了一种与果蝇A病毒较相似的新病毒,克隆出其依赖RNA的RNA聚合酶(RdRP)基因1-1 932位核酸序列,经Blast比对和系统进化分析,在氨基酸序列中发现RdRP掌型亚结构域保守区呈现复制酶置换四体病毒科(Permutotetraviridae)病毒所具有的"C-A-B"排列样式,确定该病毒是一种新的类复制酶置换四体病毒,暂命名为Laodelphax striatellus permutotetra-like virus(LsPLV)。这是首次在半翅目昆虫中发现类复制酶置换四体病毒。本研究表明灰飞虱体内昆虫病毒种类较为丰富,为今后利用昆虫病毒生物防治灰飞虱奠定了基础。

Discovery of Viruses from Small Brown Planthopper by Small RNA Deep Sequencing

Small brown planthopper(SBPH)(Laodelphax striatellus Fallén)is an important agricultural pest.As a virus vector,it can transmit some plant viruses,which cause viral diseases of grain crops,including rice,wheat and maize.At present,there is no comprehensive understanding of insect virus species in SBPH,thus it is difficult to conduct relevant research on SBPH management by exploiting insect viruses.In this paper,in order to excavate insect virus resources,the virus species in SBPH were identified by small RNA deep sequencing technology.The results showed that 13 viruses were found via sequencing data alignment,involving in 8 families and 2 unclassified viruses.Besides the dominant rice stripe virus,the rest were specialized parasitic insect viruses,including 5 positive-stranded RNA viruses,2 single-stranded DNA viruses and 5 double-stranded DNA viruses.Among them,a new virus similar to Drosophlia A virus was identified,and the 1-1 932 nt nucleotides of viral RNA-dependent RNA polymerase(RdRp)gene was obtained.After Blast and phylogenetic analysis,the unusual “C-A-B” permutation was found in the palm subdomain conserved region of RdRp,which was a unique arrangement pattern of Permutotetraviridae viruses,thus it was considered that the virus was a novel permutotetra-like virus,temporarily named Laodelphax striatellus permutotetra-like virus(LsPLV).A permutotetra-like virus was first identified in Hemiptera insect.The study suggests that insect virus species are abundant in SBPH,which lays the foundation for biological control of SBPH by exploiting insect viruses in the future.