植食性昆虫寄主转移需要在行为、形态和生理等方面产生一系列适应，对植物次生物质的解毒是其中的关键。除了昆虫自身基因的适应性改变之外，肠道微生物能够协助宿主昆虫克服取食障碍，即所谓的“肠道微生物助力假说”。但目前支持这一假说的实例还非常有限。本研究拟以叶甲科昆虫为研究对象，开展如下工作：（1）利用16S rRNA基因pyrotag测序技术对甲虫肠道微生物的群落结构进行解析；（2）通过16S rRNA基因pyrotag测序技术和生活史研究揭示叶甲肠道共生微生物的来源和传播机制；（3）采用人工饲料添加抗生素的方法处理，通过测定幼虫死亡率、发育速率以及成虫繁殖力等指标来分析肠道微生物对跳甲寄主植物利用的影响；（4）结合宏基因组和宏转录组技术对肠道微生物群落的基因功能进行预测和部分验证，以此探讨共生微生物对叶甲寄主植物转移的影响。本研究的开展将有助于全面和深入理解植食性昆虫寄主专化和物种形成机制。

Adaptations of herbivorous insects in behavior, morphology and physiology are required for successful host shifting. Novel plant secondary metabolites are usually great challenge for herbivorous insects. The “gut microbial facilitation hypothesis” suggested that gut microbes may facilitate insect herbivory of chemically defended plants. However, studies directly addressing this hypothesis are relatively few. In present study, using leaf beetle systems, we hope to (1) test the hypotheses that host plant structure gut bacterial communities by 16S rRNA pyrotag analysis; (2) address the origin and transmission strategy of gut symbionts by life history study and 16S rRNA pyrotag analysis; (3) estimate the potential function of gut symbionts by antibiotic treatment; and (4) compare the community functions based on metagenomic and metatranscriptomic analyses. The study will provide deeper insight into host plant specialization and speciation of herbivorous insects.