CAREER: Leveraging soil viromics to unravel ecological patterns in complex communities

土壤微生物对维持植物生长的养分进行循环，这些微生物很容易受到病毒感染。在海洋中，病毒每天杀死多达40%的微生物细胞，影响食物网并释放营养物质。一茶匙土壤可以容纳数千种病毒，但病毒在土壤中的作用仍然是一个谜。关于哪些病毒在哪里、何时或为什么存在，人们知之甚少。这个项目将研究土壤病毒群落在空间和时间上的差异。研究人员将研究水分如何影响病毒动态，以及土壤病毒多样性是如何保持的。这项工作需要对大数据集进行计算分析。一门新的“面向生物学家的生物信息学”课程将为本科生提供这些技能的实践培训。该课程将接触到STEM的转学学生和其他代表性不足的群体，促进STEM工作队伍的多样化发展。该项目将阐明加州戴维斯附近的加州大学戴维斯·杰普森草原自然保护区土壤病毒的时空动态。利用病毒组学(病毒大小组分的元基因组学)，将在经历不同数量混合的两个草原生境内和跨草原生境比较土壤病毒群落的生物地理学和演替模式。将探索病毒在季节性干燥土壤中存活的谜团，以研究病毒休眠和种子库在维持土壤病毒多样性方面的作用。首先，研究人员将建立当地的生物地理模式，并评估两个草原生境中土壤病毒群落的距离-衰变关系。接下来，他们将在扩散受限和混合良好的土壤中比较年度内和年际病毒群落在空间上的演替模式。最后，他们将应用一套DNA测序和实验方法来识别干燥土壤的细胞和非细胞部分中的病毒。该项目还将试行一门本科生生物信息学课程，包括由博士后研究人员团队共同领导的动手计算分析模块。除了为本科生提供培训和研究机会外，该课程还将促进对博士后导师的教学培训。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。

Soil microbes cycle nutrients that sustain plants, and these microbes are susceptible to viral infection. In the oceans, viruses kill up to 40% of microbial cells daily, impacting food webs and releasing nutrients. A teaspoon of soil can harbor thousands of viral species, but the role of viruses in soil remains a mystery. Little is known about which viruses are where, when, or why. This project will investigate how soil viral communities differ over space and time. The researchers will study how water content affects viral dynamics and how soil viral diversity is maintained. This work will require computational analyses of large datasets. A new ‘Bioinformatics for Biologists’ course will provide undergraduate students with hands-on training in these skills. The course will reach transfer students and other underrepresented groups in STEM, promoting the development of a diverse STEM workforce.This project will elucidate the spatiotemporal dynamics of soil viruses at the UC Davis Jepson Prairie Natural Reserve near Davis, CA. Using viromics (metagenomics of the viral size fraction), soil viral community biogeography and successional patterns will be compared within and across two grassland habitats that experience different amounts of mixing. The mystery of viral survival in seasonally dry soils will be explored to examine the roles of viral dormancy and seed banks in maintaining soil viral diversity. First, the researchers will establish local biogeographical patterns and evaluate the distance-decay relationship for soil viral communities in two grassland habitats. Next, they will compare intra- and inter-annual viral community successional patterns over space in dispersal-limited and well-mixed soils. Finally, they will apply a suite of DNA sequencing and experimental approaches to identify viruses in the cellular and acellular fractions of dry soils. This project will also pilot an undergraduate bioinformatics course, consisting of hands-on computational analysis modules co-led by teams of postdoctoral researchers. In addition to training and research opportunities for undergraduates, the course will facilitate pedagogical training for the postdoctoral instructors.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.