南瓜实蝇寄主适应的分子机制研究

Host adaptation is key factor for herbivorous invasive insects during their process of colonization and expansion toward new area.Host expansion is one of important aspect of host adaptation.Bactrocer tau, is one of high dangerous species of tephritide fly. It is charaterized obviously with host range expansion from melon to non-melon plants during its nearly one century expansion in China, the area of its major distribution.Host expansion is key reason to cause its enlarging distribution and serious damage and also is important resion of its ecological adaptation studying. This project focus on Batrocera tau to carry out molecular study about host adaptation. Based on identify the host range and evaluate the ability of host adaptation, we will performed de novo assembly of transcriptome using high-throughput mRNA sequencing to reveal our functional insights into host adaptation for B.tau by analysis on gene expression, function annotation and classification of differential expression gene, metabolize pathways, protein interaction. We try to learn about which types of gene differential expression are associated with host adaptation and the function and category of these genes. We also try to find host adaptation of B. tau involve which metabolize pathways. By these analysis, the molecular mechanism of host adaptation for B. tau will be revealed in a whole and deep insight. The results will be paratical value in assessing the expansion ability of B.tau and providing basic information about its controlling, eliminating and constructing cross-border ecological security system in China. The research will enrich transcripome genetic information of tephritidae fly. Meanwhile, the research will strengthen our understanding for ecological adaptation mechanism of fruit flies and consummate the theory of biological invasion. The research also will be model reference and method reference for other flies in the similar studying filed.

寄主适应是植食性入侵昆虫成功定殖扩张的重要方面,寄主扩展是寄主适应中的重要内容之一。南瓜实蝇属重要经济入侵实蝇,在其扩散过程中，寄主由单一的瓜类向非瓜类植物扩展,寄主扩展被认为是该实蝇在我国广大区域扩散危害的关键原因。本项目以南瓜实蝇为对象研究寄主适应的机制，一方面为探索实蝇昆虫寄主适应的一般规律，也是深入阐释该实蝇大范围扩散的关键。本研究拟从功能基因层面探究南瓜实蝇对寄主适应的分子机制。研究首先通过野外调查取样与室内生物及分子试验,明确我国南瓜实蝇寄主范围,辨析各寄主种群遗传差异，评估其对寄主的适应力。在此基础上，采用高通量测序法开展南瓜实蝇的转录组测序分析,明确与寄主适应有关的基因差异性表达,阐释差异基因的功能及相互关联，揭示有关的代谢通路,最终探究南瓜实蝇寄主适应的分子机制。结果将为该虫害的预警、防控提供新思路,为深化实蝇生态适应机制认识提供科学数据,具有重要应用前景和理论探索价值。

本项目以南瓜实蝇为研究对象，采用高通量测序方法进行南瓜实蝇的寄主适应性研究。研究基本按照原定计划开展，已进行了南瓜实蝇在全国的样品收集,并分析了中国及周边东南亚国家南瓜实蝇种群的遗传结构，在此基础上选取遗传结构差异较大的地区开展了南瓜实蝇寄主的调查。应用叶绿体分子标记扩增了南瓜实蝇肠道的寄主种类,但未成功。在实验室内，进行了寄主选择实验，并利用不同寄主对南瓜实蝇进行了继代饲养，应用微卫星分子标记分析了寄主群的遗传结构，最后用高通量测序法分析了不同寄主饲喂后南瓜实蝇转录组的变化,明确与寄主适应有关的基因差异性表达,阐释差异基因的功能及相互关联，揭示有关的代谢通路,最终探究南瓜实蝇寄主适应的分子机制。结果将为该虫害的预警、防控提供新思路,为深化实蝇生态适应机制认识提供科学数据,具有重要应用前景和理论探索价值。以研究结果已发表2篇SCI论文，申请专利1项,在实审答复阶段, 还有2篇论文待发。