Genetic Basis of Coleopteran Vectorial Capacity for Bean pod mottle virus Transmission

为什么一些食叶节肢动物传播植物病原体，而另一些不？此外，为什么在一个病媒物种中，通常只有一小部分人精通传播某种病原体？相当数量的鞘翅目甲虫传播病毒，导致经济上重要的蔬菜和作物的疾病。然而，甲虫种内和种间在窝藏和传播病原体的能力（即它们的传病媒介能力）方面的变化程度是显著的。载体的遗传组成无疑对其对病原体感染和传播的易感性有重要贡献，但影响载体能力的特定基因的表征已被证明是难以捉摸的。拟议研究的长期目标是了解昆虫传播病原体的遗传相互作用和机制。鉴定破坏载体介导的病原体传播的基因将导致疾病控制的新的和有前途的途径。拟议的研究将利用大豆病理系统的独特属性，由三种甲虫组成，它们在传播北美流行的大豆病毒豆荚斑驳病毒（BPMV）的能力方面表现出个体和物种水平的差异。我以前的研究强烈表明，BPMV传播能力的“遗传关键”在于甲虫自己的免疫力，这是在进食过程中沉积在叶片伤口部位。考虑到昆虫效应基因在编码改变植物防御的蛋白质中的作用，我假设甲虫的抗病剂中分泌的效应基因的补充也会影响宿主植物对虫媒病原体入侵的易感性。为了探索这一点，拟议的研究将整合甲虫趋避性转录组的比较和载体能力和基因组变异性的数据，以确定，然后测试候选效应子对载体能力的影响。 ·目标1。描述效应基因的抗性组成的种间和种内差异。 ·目标2。开发基于RNAi的工具，以功能性地表征目标1中确定的候选效应子的作用。 ·目标3。确定BPMV传播率和候选基因序列多态性在自然人群中的变异程度。 我希望能确定和功能牵连的基因，有助于BPMV的载体能力的差异和甲虫物种之间的一个子集。此外，拟议的工作将导致更好地了解驱动昆虫传播疾病的遗传，进化和环境因素。

Why do some leaf-feeding arthropods transmit plant pathogens while others do not? Moreover, why typically are only a small minority of individuals within a vector species proficient at transmitting a particular pathogen? A considerable number of coleopteran beetles transmit viruses that cause disease to economically important vegetables and crops. However, the degree of variation within and among beetle species in their ability to harbor and transmit pathogens is remarkable (i.e. their vector competence). The genetic makeup of the vector undoubtedly contributes significantly to its susceptibility to pathogen infection and transmission, yet characterization of specific genes that influence vector competence has proven elusive. The long-term goal of the proposed research is to understand the genetic interactions and mechanisms of pathogen transmission by insects. Identifying genes that disrupt vector-mediated pathogen transmission will lead to novel and promising avenues for disease control. The proposed research will harness the unique attributes of a soybean pathosystem, consisting of three beetle species that exhibit individual and species level variation in their ability to vector a soybean virus that is prevalent in North America, Bean pod mottle virus (BPMV). My previous research strongly suggested that the ‘genetic key’ to BPMV transmission capability lies in the beetle’s own regurgitant, which is deposited at leaf wounding sites during feeding. Given the role of insect effector genes in encoding proteins that alter plant defenses, I hypothesized that the complement of effectors secreted in the beetle's regurgitant also impacts host plant susceptibility to insect-borne pathogen invasion. To explore this, the proposed research will integrate comparisons of beetle regurgitant transcriptomes and data on vector competence and genomic variability to identify, and then test candidate effectors for their influence on vector competence. • Objective 1. Characterize interspecific and intraspecific differences in the regurgitant composition of effector genes. • Objective 2. Develop RNAi-based tools to functionally characterize the role of candidate effectors identified in Objective 1. • Objective 3. Determine the extent of variation in BPMV transmission rates and candidate gene sequence polymorphism in natural populations. I expect to identify and functionally implicate a subset of genes that contribute to the differences in BPMV vectorial capacity within and among beetle species. Further, the proposed work will lead to a better understanding of the genetic, evolutionary and environmental factors that drive insect-vectored disease transmission.