BRC-BIO - Expanding the ‘community’ in Community Genetics: Infracommunity genomics of duck symbionts to determine the eco-evolutionary factors underpinning holobiont evolution.

如何在生态时间和进化时间(即许多世代)中保持宿主-寄生虫的相互作用是一个重要的生物学问题，在医学、公共卫生和保护方面具有现实应用。然而，人们经常忽视的是，单个宿主可以包含不同的寄生虫群落(即社区下的寄生虫)。这项拟议的研究侧重于鸭子宿主，并试图了解它们的寄生虫群落结构和可预测性。鸭子传播几种对人类重要的疾病，包括禽流感病毒(AIV)和人类尾矿性皮炎(HCD)。作为一个群体，鸭子可以根据生态特征(栖息地选择、取食行为)分为两类，即浅水鸭和潜水鸭。先前的研究表明，涉水鸭可能支持更高的AIV和HCD传播率。这项工作将描述美国东部四种涉水和四种潜水鸭的下层群落，以确定下层群落是否特定于宿主物种和/或生态群体。我们将深入研究恢复的寄生虫种群的遗传学，以确定宿主物种和/或生态群体是否有助于解释关键的公共卫生参数，这些参数具有较高的传播率。人类引起的环境变化导致了鸭子种群的显著变化，一些物种在改变的栖息地中茁壮成长，另一些物种正在衰落。因此，迫切需要了解鸭类寄生虫亚群落的生态和进化，以便在不断变化的世界中更好地模拟AIV和HCD等疾病。在单个宿主内部，共生体群落(群落下)聚集在一起，以响应生态和进化过程。共享的宿主环境是否以协调一致的方式影响下层社区的结构、组装和微观演变？这项拟议的研究采用了群落遗传学的方法，以提供对共享寄主环境中物种内部和跨物种的进化过程的强有力的见解。这项工作将调查8种鸭子的蠕虫(寄生蠕虫)和病毒群落，根据宿主特征，这8种鸭子可分为两个不同的生态类群(涉水和潜水物种)。拟议的研究将使用长期阅读的牛津纳米孔测序来1)描述不同宿主和生态群体的群落下结构，以及2)比较种群遗传结构和恢复的核心分类群的多样性(即70%的流行率)。融合群落生态学和种群遗传学将有助于揭示群落下组装、微进化的生态决定因素，并最终为全息组的进化提供洞察力。先前对两种蠕虫(吸虫：旋毛虫)和禽流感病毒(AIV)的研究表明，更高的流行率、遗传多样性和更大的有效大小与涉猎者相关，这表明宿主特征决定了群落下组装和宿主内的微进化模式。了解社区下集合的可预测性和分类可扩展性，并确定哪些生态因素支持传播，可以提高我们模拟与水禽相关的人畜共患病的能力。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

How host-parasite interactions are maintained over ecological time and evolutionary time (i.e. many generations) is a significant biological question, with real-world applications in medicine, public health, and conservation. It is often overlooked, though, that a single host can contain a diverse community (i.e. infracommunity) of parasites.. The proposed research focuses on duck hosts and seeks to understand their parasite infracommunity structure and predictability. Ducks transmit several diseases of human importance, including Avian Influenza Virus (AIV) and Human Cercarial Dermatitis (HCD). As a group, ducks can be divided based on ecological traits (habitat selection, feeding behaviors) into two groupings, dabbling and diving ducks. Prior studies have suggested that dabbling ducks may support a higher rate of transmission of AIV and HCD. This work will characterize infracommunities of four dabbling and four diving duck species within the Eastern USA, to determine if infracommunities are specific to host species and/or ecological group. We will look deeply into the genetics of recovered parasite populations to determine if host species and/or ecological group help explain critical public health parameters, such has higher rates of transmission. Human-induced environmental change has resulted in significant changes to duck populations, such that some species are thriving in altered habitats, and others are in decline. There is thus an urgency to understand the ecology and evolution of duck parasite infracommunities to better model diseases such as AIV and HCD in a changing world. Within an individual host, a community of symbionts (infracommunity) assembles in response to both ecological and evolutionary processes. Does the shared host environment act in a concerted way to shape the structure, assembly, and microevolution of infracommunities? The proposed research takes a community genetics approach to provide robust insights into the evolutionary processes within and across species of a shared host environment. This work will investigate the helminth (parasitic worms) and viral communities of eight duck species, which can be divided into two distinct ecological groups (dabbling vs. diving species) based on host-traits. The proposed research will use long-read Oxford Nanopore Sequencing to 1) characterize infracommunity structure across hosts and ecological groups and 2) compare population genetic structure and diversity of recovered core taxa (i.e. 70% prevalence). Merging community ecology and population genetics will help uncover the ecological determinants of infracommunity assembly, microevolution and ultimately provide insights into the evolution of the hologenome. Prior work with both helminths (Trematoda: Trichobilharzia) and Avian Influenza Virus (AIV) have shown higher prevalence, genetic diversity, and larger effective sizes are associated with dabblers, suggesting host-traits shape infracommunity assembly and within-host microevolutionary patterns. Understanding the predictability and taxonomic scalability of infracommunity assembly, and identifying what ecological factors support transmission, could improve our ability to model zoonotic waterborne diseases associated with waterfowl.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.