Cellular and transcriptional regulation of the seafood toxin domoic acid

海鲜毒素软骨藻酸的细胞和转录调控

• 批准号: 10205070
• 负责人: JOHN KILPATRICK BRUNSON
• 金额: $ 2.39万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10205070
• 关键词: Academic Training; Alaska; Algal Blooms; American; Anabolism; Analytical Chemistry; Bar Codes; Biological Models; Cell physiology; Cells; Chloroplasts; Communities; Data; Data Set; Detection; Diatoms; Doctor of Philosophy; Ecosystem; Elements; Environment; Environmental Risk Factor; Enzyme-Linked Immunosorbent Assay; Enzymes; Escherichia coli; Eukaryota; Evolution; Fisheries; Food Supply; Frequencies; Future; Gene Cluster; Gene Expression; Gene Expression Profiling; Genes; Genetic; Genetic Engineering; Genetic Transcription; Genome; Goals; Health; High Pressure Liquid Chromatography; Human; Knowledge; Laboratories; Laboratory culture; Mass Spectrum Analysis; Mentors; Methodology; Methods; Modeling; Molecular; Molecular Genetics; Monitor; Neurotoxins; North America; Oceans; Pacific Northwest; Pathway interactions; Physiology; Production; Prokaryotic Cells; RNA; Regulation; Research; Research Personnel; Research Proposals; Risk; Saccharomyces cerevisiae; Sampling; Seafood; Severities; Signal Transduction; System; Techniques; Toxic effect; Toxin; Transcript; Transcriptional Regulation; Work; base; cell growth regulation; climate change; design; domoic acid; enzyme activity; experimental study; genetic manipulation; genetic testing; harmful algal blooms; improved; in vivo Model; metatranscriptomics; ocean ecosystems; professor; programs; reconstitution; shellfish toxicity; synthetic biology; tool; training opportunity; transcriptome; transcriptome sequencing

Project Summary/Abstract Oceanic harmful algal blooms (HABs) pose a major environmental threat to human health, coastal ecosystems, and marine food supplies. Due to climate change, HABs are anticipated to continue increasing in severity and frequency, impacting millions in coastal communities. The largest HAB ever recorded, comprised primarily of toxic Pseudo-nitzschia diatoms, spanned the North American west coast from Alaska to the Baja peninsula during 2015. High levels of the neurotoxin domoic acid (DA) produced by this bloom resulted in major fishery closures in the Pacific Northwest to protect human health. Although bloom monitoring and toxin detection is quite sophisticated, relatively little is known about the underlying basis for toxin production among marine HAB species. Understanding the regulation and expression of the genes encoding HAB toxin biosynthesis could improve bloom monitoring by introducing a genetic component to help predict a bloom’s potential for toxicity. The goal of this proposal is to characterize the cellular and transcriptional regulation of DA biosynthesis by using laboratory model systems, cultured Pseudo-nitzschia spp. isolates, and environmental samples. My recent work has uncovered the clustered genes that encode the DA biosynthetic pathway in Pseudo-nitzschia. I now plan to extend my research to study DA biosynthesis (dab) genes in diatom systems. By describing where DA biosynthesis takes place in the cell, we can place DA biosynthesis in the context of overall cellular physiology. In addition, tracking dab gene expression both in culture and in environmental samples can help us correlate gene transcription to bloom toxicity. I hypothesize that a full characterization of the cellular and transcriptional regulation of toxin biosynthesis will enable us to monitor Pseudo-nitzschia HAB toxicity at the transcript level. Our findings will also help the community understand the oceanic conditions that induce DA production in blooms. To achieve these goals, I will explore the subcellular localization of the Dab enzymes using the model diatom Phaeodactylum tricornutum as a heterologous host using diatom-specialized molecular techniques. Next, I will explore dab gene expression in isolates of Pseudo-nitzschia spp. grown under a variety of DA-inducing culture conditions to explore environmental inputs to toxicity. Finally, I will apply our findings from the culturing experiments to the larger environment by generating metatranscriptomics datasets from weekly filter samples collected in Monterrey Bay before, during, and after the 2015 North American Pseudo-nitzschia bloom. This proposal is designed to supplement my prior research on DA biosynthesis, allowing me to pursue further academic training opportunities together with my Ph.D. co-advisors, Professors Moore and Allen. My advisors have been chosen for their diverse and complementary scientific expertise in order to cover all elements of the proposed research.

项目概要/摘要 海洋有害藻华 (HAB) 对人类健康和沿海地区构成重大环境威胁 由于气候变化，有害生态系统预计将继续增加。 严重程度和频率，影响了沿海社区的数百万人，这是有记录以来最大的HAB。 主要由有毒的拟菱形硅藻组成，分布在从阿拉斯加到巴哈的北美西海岸 2015 年期间，该半岛出现了高浓度的神经毒素软骨藻酸 (DA)，导致了严重的 太平洋西北地区的渔业关闭以保护人类健康，尽管进行水华监测和毒素检测。 是相当复杂的，对于海洋有害细菌产生毒素的根本基础知之甚少 了解编码 HAB 毒素生物合成的基因的调控和表达可以。 通过引入遗传成分来帮助预测水华潜在的毒性，从而改善水华监测。 该提案的目标是表征 DA 生物合成的细胞和转录调控 通过使用实验室模型系统、培养的拟菱形藻分离株和环境样本。 最近的工作发现了伪菱形藻 I 中编码 DA 生物合成途径的簇状基因。 现在计划通过描述硅藻系统中的 DA 生物合成 (dab) 基因来扩展我的研究。 DA生物合成发生在细胞内，我们可以将DA生物合成置于整个细胞生理学的背景下。 此外，跟踪培养物和环境样本中的 dab 基因表达可以帮助我们关联 我领导了对细胞和转录的全面表征。 毒素生物合成的调控将使我们能够在转录水平上监测拟菱形藻HAB的毒性。 我们的研究结果还将帮助社区了解导致水华产生 DA 的海洋条件。 为了实现这些目标，我将使用该模型探索 Dab 酶的亚细胞定位 使用硅藻专用分子技术将硅藻三角褐指藻作为异源宿主。 我将探索在各种 DA 诱导下生长的拟菱形藻分离株中的 dab 基因表达。 最后，我将应用我们的培养结果。 通过每周过滤样本生成宏转录组数据集，对更大的环境进行实验 采集于 2015 年北美拟菱形藻盛开之前、期间和之后的蒙特雷湾。 该提案旨在补充我之前对 DA 生物合成的研究，使我能够追求 与我的博士生导师摩尔和艾伦教授一起进行进一步的学术培训。 顾问的选择具有多样性和互补性的科学专业知识，以涵盖所有要素 拟议的研究。