草地贪夜蛾4个性信息素结合蛋白基因的克隆及表达模式分析

Cloning and expression profile analysis of four pheromone-binding protein genes in the fall armyworm,Spodoptera frugiperda

草地贪夜蛾是世界性的重大害虫,2019年1月入侵我国并迅速扩散到20多个省市。性诱剂是对草地贪夜蛾进行监测和诱杀的有效手段,但是其作用识别机制仍不清楚,限制了高效性诱剂的研发和应用。性信息素结合蛋白(PBPs)在鳞翅目昆虫包括草地贪夜蛾性信息素识别过程中起重要作用。本研究从草地贪夜蛾中克隆了4个编码PBPs的cDNA序列,命名为SfruPBP1-SfruPBP4。4个SfruPBP s均含有完整的开放阅读框,所编码的蛋白具有性信息素结合蛋白的典型特征:N-端有信号肽、具有保守的6个半胱氨酸残基。系统进化分析显示SfruPBPs与斜纹夜蛾和海灰翅夜蛾PBPs的亲缘关系最近,且4个SfruPBPs被聚在不同的进化分支。4个SfruPBP s基因均由3个外显子和2个内含子组成,内含子插入位点高度保守。此外,4个SfruPBP s在草地贪夜蛾基因组上呈串联排列。SfruPBP1、SfruPBP2和SfruPBP3在成虫触角中特异性表达,其中SfruPBP1和SfruPBP2在雄成虫触角中的表达水平显著高于雌虫,而SfruPBP3在雌雄触角中的表达水平无显著差异。SfruPBP4特异性表达于雄成虫腹部。本研究结果为揭示草地贪夜蛾性信息素识别机制奠定了基础。

The fall armyworm,Spodoptera frugiperda,is a major agricultural pest wordwide.This pest has invaded and rapidly spread in more than 20 provinces in China by January 2019.Use of pheromone lures is an effective method for population monitoring and mass-trapping of S.frugiperda.However,the mechanism of sex pheromone reception is not yet clear in this insect species,limiting the development and application of pheromone lures with high efficiency.Pheromone-binding proteins(PBPs)play critical roles in the recognition of intraspecific sex pheromones in most lepidopteran species,including S.frugiperda.In this study,four cDNA sequences encoding PBPs were cloned from S.frugiperda and named as SfruPBP1-SfruPBP4.The four SfruPBP s all contained complete open reading frames,and the proteins encoded by these genes all have the remarkable features of PBPs:The N-terminal signal peptides and six positionally conserved cysteine residues.Phylogenetic analysis result showed that the four SfruPBPs were closely related to PBPs from Spodoptera litura and S.littoralis,and that the four SfruPBPs fell into different branches.The four SfruPBP s all consisted of three exons and two introns,with highly conserved intron insertion sites.Moreover,the four SfruPBP genes were tandemly arrayed in the genome of S.frugiperda.SfruPBP 1,SfruPBP2 and SfruPBP3 were specifically expressed in the antennae of adults;of these,the transcription levels of SfruPBP1 and SfruPBP2 in male antennae were significantly higher than those in female antennae,while the variation in SfruPBP3 transcription between male and female antennae was not significant.SfruPBP4 was specifically expressed in the abdomen of male adults.This study pave the way for revealing the mechanism underlying pheromonal recognition in S.frugiperda.