Integrating population genomics and microbial metagenomics of the lone star tick, an expanding arthropod disease vector

整合群体基因组学和微生物宏基因组学的孤独星星蜱，一个扩大 节肢动物病媒 项目总结/摘要 蜱是美国最重要的致病病原体载体。孤独的星星滴答作响， 美洲钝眼蜱是多种病原微生物的有效传播媒介。有几 我们对一种节肢动物疾病--孤星星蜱的基础生物学的理解存在着严重的知识缺口 传播媒介，正在迅速扩大其地理分布到中西部和东北部。知之甚少 蜱虫基因组的多样性和蜱虫微生物组的微生物多样性如何影响 特定的病原体来感染蜱虫。这项研究的主要目的是产生一个整合的遗传 蜱传疾病的流行病学，包括载体的基因组多样性， 它的微生物组和已知病原体的流行。总体假设是基因组多样性 蜱媒生物多样性与微生物物种多样性呈正相关，与病原体呈负相关 普遍性。首席研究员将使用下一代DNA测序来测试总体 通过三个具体目标实现本项目的主要目标：（1）调查空间 西、北方孤星星蜱种群间基因组变异的分布 边界目前的假设是，基因组多样性的一个渐变群对应于压力的增加。 气候条件在物种范围的边缘，这表明，范围的扩大与 微进化变化(2)表征孤星星蜱的微生物组并评估其与宿主的关系 基因组多样性工作假设是，蜱虫的基因组多样性越大， 蜱的物种多样性，表明宿主基因型影响微生物组组成。(3)审查的影响 基因组多样性和微生物多样性对病原体感染的影响。工作假设是 个体蜱的高基因组和微生物多样性减少了病原菌的感染，这表明 蜱虫体内微生物的竞争性相互作用决定了特定蜱传病原体的流行 在更广的范围内。这项研究具有创新性，因为它将（a）独特地将人口研究中的方法联系起来， 基因组学、细菌宏基因组学和媒介传播的病原体的群落生态学;（B）产生基因组 这些数据将为今后的A. americanum和其他蜱;和（c）照亮 在实验室饲养的蜱虫中考虑基因组和微生物组多样性的重要性， 病原体传播、宿主免疫和杀螨剂。这项研究意义重大，因为它将揭示 对可能影响病原体动态的单个蜱虫内的微生物相互作用的研究。发现细菌 竞争性抑制蜱内病原体感染的谱系或集合体将是 控制由蜱和其他节肢动物传播的疾病。此外，这项拟议研究将加强 佩珀代因大学的研究基础设施，并将提供重要的机会，本科 对生物医学科学和载体生物学感兴趣的学生。

Integrating population genomics and microbial metagenomics of the lone star tick, an expanding arthropod disease vector PROJECT SUMMARY/ABSTRACT Ticks are the most important vectors of disease-causing pathogens in the United States. The lone star tick, Amblyomma americanum, is a competent vector of various pathogenic microorganisms. There are several critical knowledge gaps in our understanding of the basic biology of the lone star tick, an arthropod disease vector that is rapidly expanding its geographic distribution into the Midwest and Northeast. Little is known about how the diversity of the tick’s genome and the microbial diversity of the tick’s microbiome affect the ability of specific pathogens to infect a tick. The main objective of this research is to generate an integrated genetic epidemiology for tick-borne diseases that incorporates the genomic diversity of vector, the species diversity of its microbiome, and the prevalence of known pathogens. The overarching hypothesis is that genomic diversity of tick vectors is positively associated with microbial species diversity and negatively associated with pathogen prevalence. The Principal Investigator will use next-generation DNA sequencing to test the overarching hypothesis and achieve the main objective of this project through three specific aims: (1) Investigate the spatial distribution of genomic variation among populations of lone star tick near the western and northern species range boundaries. The working hypothesis is that a cline of genomic diversity corresponds to increasingly stressful climatic conditions at the edges of the species range, suggesting that range expansion coincides with microevolutionary change. (2) Characterize the microbiome of lone star tick and assess its relationship to host genomic diversity. The working hypothesis is that greater genomic diversity of ticks permits a greater microbial species diversity in ticks, suggesting that host genotype affects microbiome composition. (3) Examine the effects of genomic diversity and microbial diversity on pathogen infection in individual ticks. The working hypothesis is that high genomic and microbial diversity of individual ticks reduces infection by pathogenic bacteria, suggesting that competitive interactions of microbes inside of ticks govern the prevalence of specific tick-borne pathogens at broader scales. This study is innovative because it will (a) uniquely bridge methodologies in population genomics, bacterial metagenomics, and community ecology of vector-borne pathogens; (b) generate genomic data that will be a valuable resource for future investigations of A. americanum and other ticks; and (c) illuminate the importance of accounting for genomic and microbiome diversity in laboratory-reared ticks used in studies of pathogen transmission, host immunology, and acaricides. This study is significant because it will shed light on the microbial interactions within individual ticks that may influence pathogen dynamics. Discovering bacterial lineages or assemblages that competitively inhibit infection by pathogens within ticks will be a significant step in controlling diseases vectored by ticks and other arthropods. Furthermore, this proposed study will enhance the infrastructure for research at Pepperdine University and will provide crucial opportunities to undergraduate students interested in careers in biomedical sciences and vector biology.