烟蚜茧蜂滞育关联基因的转录组学分析

Transcriptome Analysis of Diapause-associated Genes of Aphidius gifuensis Ashmaed

烟蚜茧蜂Aphidius gifuensis Ashmaed是一种优良的内寄生性天敌昆虫,可有效控制桃蚜等多种蚜虫为害。通过调控温光环境可诱导烟蚜茧蜂进入滞育,既能提升子代烟蚜茧蜂的适应能力和寄生能力,又能显著延长天敌产品的货架期,促进天敌昆虫在害虫生物防治中的应用。本文通过对烟蚜茧蜂的正常发育状态(ND)、滞育状态(D)及滞育解除状态(PD)进行RNA测序,改变并丰富了以往仅对正常和对照组进行分析的常规做法,重点研究只在滞育状态才特异表达、而在正常发育和滞育解除后无显著变化的转录组学波动规律。经分别构建正常发育、滞育、滞育解除样本组,再经RNA提取与纯化,c DNA合成,c DNA文库构建,文库质检合格后进行de novo双端测序,根据对9个样本的测序结果,获取unigene 40477个,获得ND组与D组差异表达基因458个,D组与PD组差异表达基因298个,进一步筛选出D组与ND及PD组显著差异、但ND组与PD组无显著差异的滞育关联基因59个,对后者进行了GO富集、KEGG通路富集等表达分析,根据功能注释发现这些滞育关联基因与自身防御、耐寒性、脂类代谢、表皮黑化、转录调控等途径相关,是影响烟蚜茧蜂滞育进程的重要调控和参与基因。

Aphidius gifuensis Ashmead is an excellent solitary endoparasitoid natural enemy, which can control a variety of aphids effectively, especially the aphid Myzus persicae（Sulzer）. Diapause plays an important role in the overwintering of A. gifuensis. By simulating the environmental conditions of winter via controlling temperature and photoperiod in the laboratory, we induced the insects to enter diapause for the purposes of enhancing adaptive capacity and parasitic ability of offspring, increasing the production of the biological control agents for pest management. Transcriptome sequencing analyses were employed to compare expression differences between no-diapause（ND）, diapause（D） and post-diapause（PD） groups. After RNA extraction and purification, c DNA synthesis, and establishment of c DNA libraries, a total of 40477 unigenes were obtained from 9 samples. We detected 458 differentially expressed genes（DEGs） between ND and D, and 298 DEGs between D and PD. And 59 diapause-associated genes were revealed to be significantly different in D/ND and D/PD, but no significant difference was found in PD/ND. With analysis of GO and KEGG enrichment on diapause-related genes, we found that these genes were primarily associated with cold resistance, autoimmune defense, lipid metabolism, insect cuticle protein and transcriptional regulation, which are the genes regulating the diapause process of A. gifuensis.