Unravelling the Complex Interactions of Algal Viruses and Their Hosts

在全球范围内，微藻或浮游植物是最重要的水生初级生产者。它们对人类事务至关重要，因为它们将无机物质转化为有机物质，从而为海洋和淡水食物网提供燃料。它们的生长决定了水生环境的生产力和质量，也决定了人类对它们的有益利用，例如维持渔业或形成令人讨厌的藻华。20世纪90年代，生物海洋学家发现，感染藻类的病毒在几乎所有水生环境中都很丰富，其中大多数具有高度物种特异性，可以溶解或杀死其藻类宿主。这些发现提出了许多关于病毒对水生食物网的影响及其在藻类生态和进化中的作用的问题。正在进行的研究表明，藻类的病毒感染可以直接和间接地影响物种竞争，水生环境中的营养循环和藻类进化。越来越多的证据表明，藻类病毒和它们的宿主以动态的方式相互作用，每一种都会影响另一种的生长和进化，但它们的相互作用是复杂的，很少可以预测，因此许多基本问题仍然没有答案。我的研究计划的长期目标是提高藻类病毒与宿主相互作用的知识。这些研究将提高我们预测浮游植物群落的组成和动态及其提供的生态系统服务的能力。在未来的几年里，我的研究团队将专注于我的计划的长期目标所包含的具体，易于处理的目标。这些研究包括藻类病毒的环境持久性研究，描述我的团队从安大略湖发现并分离的藻类病毒的财团，并描述这些病毒的遗传能力和活动。为实现这些目标，我们将进行的实验涉及实验室培养和环境采样，以及各种分子生物学和细胞生物学工具，如定量PCR，透射电子显微镜，基因组测序和下一代测序促进的基因表达研究。我的研究小组最近分离出了感染全球相关淡水微藻的病毒，并且发现我们拥有一个不同病毒和病毒载体的联盟，这些病毒共同感染宿主细胞并间接寄生其他病毒，这大大增强了我们对病毒-藻类相互作用的理解能力！这些项目将为从环境监测到分子生物学等备受追捧的研究技术提供培训机会。我的研究将通过提高我们对病毒在初级生产中的作用的理解来为水生生态系统模型提供信息，并将教会我们环境如何影响病毒活动。更广泛地说，我们的研究将有助于推进病毒生态学和进化以及病毒发病机制的知识。

Globally, microalgae, or phytoplankton, are the most important aquatic primary producers. They are critical to human affairs because they convert inorganic material into organic thereby fueling marine and freshwater food webs. Their growth determines the productivity and quality of aquatic environments, and their beneficial use by human by sustaining fisheries or forming nuisance algal blooms, as examples. In the 1990s, biological oceanographers discovered that viruses infecting algae are abundant in nearly all aquatic environments and most of them are highly species-specific and lyse, or kill, their algal hosts. These discoveries raised many questions about the influence of viruses on aquatic food webs and their role in algal ecology and evolution. Ongoing research has demonstrated that viral infections of algae can directly and indirectly affect species competition, nutrient cycling in aquatic environments, and algal evolution. Evidence is accumulating that algal viruses and their hosts interact in a dynamic manner, each influencing the growth and evolution of the other, yet their interactions are complex and rarely predictable, so many fundamental questions remain unanswered. The long-term goal of my research program is to advance knowledge of algal virus' interactions with their hosts. These studies will enhance our ability to predict the composition and dynamics of phytoplankton communities and the ecosystems services they provide. In the coming years, my research team will focus on specific, tractable objectives encompassed by my program's long-term goal. These include studies of the environmental persistence of algal viruses, characterizing a consortium of algal viruses that my group discovered and isolated from Lake Ontario, and characterizing the genetic capabilities and activities of these viruses. The experiments we will conduct to fulfill these objectives involve laboratory-based cultivation and environmental sampling, and various molecular biology and cell biology tools like quantitative PCR, transmission electron microscopy, and genome sequencing and gene expression studies facilitated by Next-Generation Sequencing. Our ability to advance understanding of virus-algae interactions is greatly enhanced by my research group's recent isolation of viruses that infect a globally relevant freshwater microalgae, and the discovery that we have in our possession a consortium of different viruses and virophages, viruses that co-infect host cells and indirectly parasitizes other viruses! These projects will provide training opportunities for highly sought research techniques ranging from environmental monitoring to molecular biology. My research will inform models of aquatic ecosystems by enhancing our understanding of the role of viruses in primary production and will teach us how the environment influences virus activity. More broadly, our studies will contribute to advancing knowledge of virus ecology and evolution, and viral pathogenesis.