为了解植物化合防御物质皂苷对专食性天敌莲草直胸跳甲Agasicles hygrophila的防御作用,测定莲草直胸跳甲2龄幼虫取食皂苷后的排泄和肠道变化,利用转录组测序筛选参与皂苷代谢的候选基因,并采用RNA干扰技术鉴定候选基因功能.结果发现,取食皂苷导致莲草直胸跳甲幼虫排泄量增加,肠道畸变,排泄量与取食皂苷浓度正相关.转录组测序发现,与对照相比,取食100 mmol/L皂苷处理的莲草直胸跳甲幼虫肠道有496条差异表达基因,其中261个上调基因和235个下调基因.GO分类和KEGG分类分析发现糖苷水解酶家族1(glycoside hydrolase family 1,GH1)基因集中在碳水化合物水解通路.利用RNA干扰技术鉴定发现,莲草直胸跳甲AghyGH1a基因沉默可导致幼虫取食皂苷后排泄量增加,肠道内容物颜色更暗沉.表明莲草直胸跳甲AghyGH1a参与皂苷代谢.
Glycoside hydrolase family gene AghyGH1a is involved in saponin metabolism in alligator weed flea beetle Agasicles hygrophila
To investigate the defensive role of the chemical defense compound saponin against larvae of the specialized biocontrol natural enemy alligator weed flea beetle Agasicles hygrophila,changes in lar-val excretion and gut were studied following feeding the second-instar larvae with saponin. Transcrip-tomic sequencing was used to analyze candidate genes involved in saponin metabolism,and the func-tions of these genes were identified by using RNA interference (RNAi). Results showed that ingestion of saponin increased larval excretion and caused intestinal distortion compared to the control,with ex-cretion levels positively correlated with saponin concentration. Transcriptome sequencing identified a total of 496 differentially expressed genes in larvae fed with saponin,including 261 up-regulated genes and 235 down-regulated genes. GO classification and KEGG classification analysis revealed enrichment of glycoside hydrolase family 1 (GH1) genes involved in carbohydrate hydrolysis pathways. Using RNAi,silencing of AghyGH1a increased larval excretion and darkened gut contents,indicating its role in saponin metabolism in this beetle.
万方数据
维普
