Ecology and biogeochemical impacts of DNA and RNA viruses throughout the global oceans

在海洋中，微生物生命位于食物链的底部，但微生物也控制着营养物质和能量的流动。虽然我们对微生物对海洋的影响的知识正在迅速发展，但我们在研究病毒的影响方面仍然远远落后。几十年来专注于常见海洋病毒(双链DNA病毒)的实验和全球调查表明，它们可以杀死许多细胞，改变细胞基因组中编码的基因，并重新编程细胞在感染期间的功能。该项目试图创建全球海洋的新陈代谢图，并量化常见病毒操纵这些微生物过程中的哪些。此外，该项目将扩展到研究较少的其他类型的病毒(RNA病毒)，以及提高我们对DNA和RNA病毒在全球模式和分布方面的知识，以评估病毒的活性。这种分析对于更好地了解各种类型的病毒如何改变微生物过程，从而推动海洋中的营养循环至关重要。除了科学，该项目还将培训两名博士后、一名研究生和五名本科生，并通过哥伦布地区的研讨会和系列讲座进行推广，并在每一年和三年为研究人员提供培训讲习班。微生物新陈代谢以影响全球海洋生物地球化学的方式改变营养物质和能量流动，但相关病毒通过死亡、水平基因转移和新陈代谢重新编程来调节这些代谢影响。由于主要是人工过程，对后一种影响的研究尤其不足，尽管早期数据暗示，它可能会影响光合作用、中心碳代谢以及氮和硫的循环。此外，尽管真核生物很可能最常被RNA病毒感染，而且RNA病毒被认为代表了海水中约一半的病毒颗粒，但关于RNA病毒多样性或生态的信息很少。最后，粒子不是活泼的？病毒的形式，这要求开发新的方法来评估活性，使用新的可用的参考基因组对照表达(例如，后转录)数据集。该项目寻求利用来自全球Tara海洋探险的广泛的生物、物理和化学数据集，以(I)从调查dsDNA病毒生物多样性向推断其新陈代谢影响和活跃的感染生态前进，以及(Ii)建立平行的RNA病毒生物多样性清单，以建立对驱动因素和群落结构的基本生态学理解。科学上，这些努力将评估十几个假说，并建立无数关于病毒在海洋微生物生态和生物地球化学中的作用的假说。该项目将培训两名博士后、一名研究生和五名本科生，其中一些人通过参与国际Tara Ocean联盟会议，以及通过课堂和研讨会访问哥伦布地区的一所学校(约240名学生)、麻省理工学院校友俱乐部的当地分会、俄亥俄州立大学的RNA生物学中心？科学星期日？提供公共宣传。系列讲座，与加拿大S土著人民的研讨会和互动活动。病毒学培训工作坊将在每一年和第三年举行，以最大限度地增加研究社区的参与和参与。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。

In the oceans, microbial life sits at the base of the food chain, but microbes also control the flow of nutrients and energy. While our knowledge of microbial impacts on the oceans is rapidly advancing, we remain far behind in studying the impact of viruses. Decades of experiments and global surveys that have focused on common ocean viruses (double-stranded DNA viruses) suggest that they kill many cells, change the genes that cells encode in their genomes, and reprogram how cells function during infection. This project seeks to create a metabolic map of the global oceans and quantify which of these microbial processes common viruses manipulate. Further, this project will expand to other types of viruses (RNA viruses) that are less well studied, as well as advance our knowledge of both DNA and RNA viruses with respect to global patterns and distributions to assess viral activity. Such analyses are critical to better understand how viruses of all types alter microbial processes and thereby drive nutrient cycling in the oceans. Beyond the science, this project will train two postdocs, a graduate student and five undergraduate students, as well as conduct outreach through Columbus-area seminars and lecture series and provide a training workshop for researchers in each years 1 and 3. Microbial metabolisms alter nutrients and energy flow in ways that impact global ocean biogeochemistry, but associated viruses modulate these metabolic impacts through mortality, horizontal gene transfer and metabolic reprogramming. The latter impact is particularly understudied due to being a largely manual process, though early data hints that it likely impacts photosynthesis, central carbon metabolism, and nitrogen and sulfur cycling. Further, though eukaryotes are likely most commonly infected by RNA viruses and RNA viruses are thought to represent about half of viral particles in seawater, very little information on RNA virus diversity or ecology exists. Finally, particles are not the ?active? form of viruses, which begs for the development of new approaches to assess activity using the newly-available reference genomes against expression (e.g., metatranscriptomic) datasets. This project seeks to leverage extensive organismal, physical, and chemical datasets from the global Tara Oceans expedition to (i) advance from surveying dsDNA viral biodiversity towards inferring their metabolic impacts and active infection ecology, and (ii) build a parallel RNA virus biodiversity inventory from which to establish foundational ecological understanding of drivers and community structure. Scientifically, these efforts will evaluate more than a dozen hypotheses and establish countless more hypotheses about viral roles in marine microbial ecology and biogeochemistry. The project will train two postdocs, a graduate student and five undergraduate students, some through engagement with international Tara Oceans Consortium meetings, as well as provide public outreach through classroom and seminar visits at a Columbus area school (~240 students), a local chapter of the MIT Alumni club, an OSU Center for RNA Biology ?Science Sundays? lecture series, and seminars and interactive activities with Canada?s indigenous people. A viromics training workshop will be held in each years 1 and 3 to maximize research community involvement and engagement.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.