RAPID: Investigation of Natural Selection and Host-microbiome-virome Interactions in an Unprecedented and Ongoing Marine Epidemic

RAPID：在前所未有的持续海洋流行病中研究自然选择和宿主-微生物组-病毒组相互作用

• 批准号: 1555058
• 负责人: Melissa Pespeni
• 金额: $ 19.65万
• 依托单位: University of Vermont & State Agricultural College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1555058&HistoricalAwards=false
• 关键词: RAPID; Investigation; Natural; Selection; Host

Large infectious disease outbreaks allow for relatively faster evolutionary changes in the host, the infectious pathogen, and the community of microorganisms living within the host (the microbiome). While these interactions are poorly understood, they're extremely important in predicting and controlling future outbreaks. The largest recorded marine epidemic ever recorded is currently ongoing in intertidal ecosystems along the west coast of North America. Sea star wasting disease (SSWD) is effecting sea star populations from South Eastern Alaska to Baja California, Mexico and local extinctions are a serious concern. Large-scale epidemics such as these are expected to become more common as the global environment and species' population distributions change. This current disease event provides a unique opportunity to better understand how hosts, the hosts' microbiome, and the disease causing pathogen change throughout an epidemic. The research proposed here will lead to a deeper understanding of these disease events from an evolutionary and ecological perspective by characterizing changes in host and pathogen due to natural selection following epidemics.This project aims to understand the impact of the microbiome and virome on host disease status and progression at the individual, population, and community levels. The work will contribute to the understanding of an organism as a sum of its inhabitants and will dissect the role of the microbial community in physiological and evolutionary responses to disease. Disease may often be due to a disruption in the balance of an organisms' complex community of microorganisms. Thus, the evolution of disease is not the coevolution of two players (host and pathogen), but rather the coevolution of all members of the host's community. The ongoing Sea Star Wasting Disease event provides a unique opportunity to investigate how this evolution plays out in a widespread epidemic. Specifically, the proposed research aims to (1) identify the targets of natural selection in host and virus populations and (2) investigate molecular mechanisms in the host, virus, and microbiome that underline resistance in hosts and virulence in virus in order to identify the tipping point between asymptomatic and symptomatic hosts. This will be accomplished using a novel sequencing technique that simultaneously collects sequence data from the transcripts of the eukaryotic host, bacterial community, and viral community. This approach allows for identification of the major players in the interaction as well as their functional roles. The understanding of this complicated coevolution will impact the fields of disease ecology and evolution as well as affect the way wildlife and human diseases are understood and, hopefully, prevented or controlled.

大规模传染病爆发使得宿主、传染性病原体和宿主体内的微生物群落（微生物组）发生相对较快的进化变化。虽然人们对这些相互作用知之甚少，但它们对于预测和控制未来的疫情爆发极其重要。目前，有史以来最大规模的海洋流行病正在北美西海岸的潮间带生态系统中发生。海星消耗性疾病（SSWD）正在影响从阿拉斯加东南部到墨西哥下加利福尼亚州的海星种群，局部灭绝是一个严重的问题。随着全球环境和物种种群分布的变化，此类大规模流行病预计将变得更加普遍。当前的这一疾病事件提供了一个独特的机会，可以更好地了解宿主、宿主的微生物组和致病病原体在整个流行病期间如何变化。 这里提出的研究将从进化和生态的角度更深入地了解这些疾病事件，通过表征流行病后自然选择引起的宿主和病原体的变化。该项目旨在了解微生物组和病毒组对个体、群体和社区层面的宿主疾病状态和进展的影响。这项工作将有助于理解有机体作为其居民的总和，并将剖析微生物群落在疾病的生理和进化反应中的作用。疾病通常可能是由于生物体复杂的微生物群落的平衡被破坏造成的。因此，疾病的进化不是两个参与者（宿主和病原体）的共同进化，而是宿主群落所有成员的共同进化。正在进行的海星消耗性疾病事件提供了一个独特的机会来研究这种演变如何在广泛的流行病中发挥作用。具体来说，拟议的研究旨在（1）确定宿主和病毒种群中自然选择的目标；（2）研究宿主、病毒和微生物组中强调宿主抵抗力和病毒毒力的分子机制，以确定无症状和有症状宿主之间的临界点。这将使用一种新颖的测序技术来实现，该技术同时从真核宿主、细菌群落和病毒群落的转录物中收集序列数据。这种方法可以识别交互中的主要参与者及其功能角色。对这种复杂的共同进化的理解将影响疾病生态学和进化领域，也会影响野生动物和人类疾病的理解以及预防或控制的方式。