外来入侵种福寿螺对四聚乙醛抗性的分子机理研究

Insecticide resistance has become a critical concern for control of many pest species. Pomacea canaliculata as a worldwide malignant invasive species leads threat to biodiversity and public health security as well as an increasing economic concern in China. The higher doses and longer duration use of insecticides such as metaldehyde to control and to reduce the prevalence of P. canaliculata is the main way and measure in China and as a result, the development of insecticide resistance has been markedly enhanced, or even causing cross-resistance. As resistance to insecticides is associated with over-expression and mutation of structural gene, resistance mechanism that leads P. canaliculata to become successful resistance remains unclear. Here, we focus on response to metaldehyde on detoxification enzymes and genome of the invasive P. canaliculata at two scales in both its resistant and susceptible ranges. Using functional genomic analysis of a de novo assembly transcriptome, the key genes potentially belonging to families related to insecticide resistance in P. canaliculata will be identified, with examining the mRNA expression profile by real-time polymerase chain reaction. To elucidate the mechanisms responsible for insecticide resistance of P. canaliculata, the relationship between expression?patterns?of resistance genes? that are associated with SNP genotype and detoxification enzymes from resistant and susceptible populations. Above findings provide unique insights into how P. canaliculata has a positive interactions on successful resistance to insecticides.

抗药性已成为有害生物控制的一个关键问题。福寿螺为恶性入侵水生生物，危害我国经济、生态和公共卫生安全。由于广泛、重复和高剂量使用四聚乙醛等杀螺剂，导致福寿螺耐药能力明显增强，甚至发生交叉抗性。由于抗药性与基因的过量表达和结构基因突变有关，福寿螺抗药性的产生受哪些抗性基因影响，而这些基因如何调控等科学问题还不清楚。本项目通过福寿螺抗性和敏感个体继代汰选，从解毒酶和基因组学两个层次研究福寿螺对四聚乙醛的应答反应；采用高通量转录组测序技术和比较表达谱技术，识别差异显著的表达基因，发掘与福寿螺抗药性相关的功能基因，并验证表达基因在转录水平上的表达差异，通过分析抗性基因mRNA表达差异及基因SNPs多态性与代谢/解毒酶活性的相关性等试验，阐明福寿螺的抗药产生的形成规律。

福寿螺为我国高危性外来入侵物种，已严重危害我国经济、生态和公共卫生安全。其抗药性已成为目前生产难以控制的重要问题。本项目通过福寿螺的3种酶活性、利用转录组和DGE测序技术对福寿螺4个不同地区群体在3个杀螺药物四聚乙醛浓度下进行分析，结果发现：（1）四聚乙醛胁迫下，福寿螺机体组织酶活性呈现为“降低—升高—降低”的趋势，可能是由农药在代谢过程中产生的次级代谢产物所引起。（2）获得福寿螺转录组数据库，发掘一批福寿螺重要性状功能基因，并利用多组学技术发掘了23个与抗药性状显著关联的候选基因；（3）新发现了2个新型的CYP450基因，国际CYP450命名委员分别命名为CYP4GR1和CYP3192A1，并验证了CYP4GR1和CYP3192A1在福寿螺抗药中的作用。这些数据将会有助于系统地阐明福寿螺对四聚乙醛抗药性的形成规律和分子机制。