Collaborative Research: A Post-Genomic Approach to Synechococcus-grazer Interactions

水环境中微生物最常见的命运是成为抗议食草动物的食物。因此，水环境中的主要碳通量是通过微生物-原生生物的相互作用来调节的。微生物试图避开食草动物的机制可能包括形态、行为和化学抗性策略，但我们对这些策略的了解还很原始，目前在有害藻华物种方面取得了最大进展。从多个蓝藻基因组的可获得性中得到的启示之一是，不同的蓝藻具有非常不同的细胞表面结构以及对共同结构的潜在不同修改。此外，在几个可用的基因组中也检测到了潜在的化学抗性策略。该项目将与具有原生生物生物学、蓝藻生态学、分子遗传学和基因组学专业知识的研究人员合作，研究原生生物与聚球藻属蓝藻之间的相互作用范围。研究人员建议利用最近获得的完整基因组和分子遗传学工具来确定不同原生动物食草动物选择的关键细胞结构。他们将使用“弹枪”方法(转座子突变和选择)来鉴定这些结构，并使用可用的突变体来研究特定的已知细胞表面结构。他们还将研究通过全基因组比较发现的一些潜在的化学防御酶在阻止放牧方面的作用。拟议的研究将提供关于各种食草动物威慑战略的作用的定性和定量信息，以及理解食草动物-猎物相互作用的新范式。拟议研究的广泛影响这项工作的更广泛影响将包括对本科生和研究生的培训，包括来自代表性不足群体的培训。科学发现将通过参加国家会议和在同行审查期刊上发表来广泛传播。这些发现可能为理解微生物-食草动物的相互作用提供了一个机制基础，这是决定海洋碳循环的主要过程之一。研究人员希望确定一个或多个模式，但在生态上相关的食草动物-蓝藻对，可以被社区用于未来的研究。此外，通过这些活动，可能发现影响真核细胞的新型海洋天然产物，具有可能的生物技术应用。

The most common fate of microbes in aquatic environments is to become a meal for a protest grazer. A major flux of carbon in aquatic environments is thus mediated through microbe-protist interactions. The mechanisms by which microbes attempt to avoid grazers likely include morphological, behavioral, and chemical resistance strategies, yet our knowledge of these is primitive and most progress is currently being made on harmful algal bloom species. One of the insights from the availability of multiple cyanobacterial genomes is that different cyanobacteria have very different cell surface structures as well as potentially different modifications of common structures. In addition, potential chemical resistance strategies have been detected in several available genomes. This project will address protest-cyanobacterial interactions with the collaboration of researchers with expertise in protist biology, cyanobacterial ecology, molecular genetics and genomics to examine the range of interactions between protists and cyanobacteria of the genus Synechococcus. The investigators propose to use the recent availability of complete genomes and molecular genetics tools to determine the key cell structures under selection by diverse protist grazers. They will use "shot-gun" approaches (transposon mutagenesis and selection) to identify these structures and use available mutants to investigate specific known cell surface structures. They will also examine the role of some potential chemical defense enzymes, found through whole genome comparisons, in deterring grazing. The proposed research will provide qualitative and quantitative information on the role of various grazer deterrence strategies and new paradigms for understanding grazer-prey interactions.Broader Impacts of the Proposed ResearchThe broader impacts of this work will include the training of undergraduate and graduate students, including those from under-represented groups. Scientific findings will be disseminated broadly though participation in national meetings and publication in peer-review journals. The findings may indicate a mechanistic basis for understanding microbe-grazer interactions, one of the major processes determining carbon cycling in the oceans. The investigators expect to define one or more model but ecologically relevant grazer-cyanobacteria pairs that could be used by the community for future studies. In addition, novel marine natural products that affect eukaryotic cells, with possible biotechnological applications, may be found through these activities.