Collaborative Research: RUI: Keystone molecules and estuarine foodwebs: chemical defense and a novel biosynthetic pathway in a common mudflat mollusc

合作研究：RUI：关键分子和河口食物网：常见泥滩软体动物的化学防御和新型生物合成途径

• 批准号: 2127112
• 负责人: Amanda Zellmer
• 金额: $ 12.86万
• 依托单位: Occidental College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2127112&HistoricalAwards=false
• 关键词: Collaborative; Research; RUI; Keystone; molecules

Estuaries are ecologically sensitive nursery habitat for many economically important coastal species. A potentially important but understudied food resource for migratory waterbirds, juvenile fish, and diverse invertebrate predators are small sea slugs (genus Alderia), which can occur in dense aggregations of over 1,000 slugs per square meter on temperate mudflats throughout the Northern Hemisphere. We hypothesize that Alderia use a recently discovered branch of metabolism to make bad-tasting molecules termed polyketides, a family of compounds that include medically important drugs. We will characterize new polyketides from these abundant slugs, test how they repel predators, and then explore how they may affect many other aspects of the ecosystem. Potential effects of these slug compounds include changing the bacteria in the mud through antibiotic effects; repelling some animal species that live in the mud while attracting others; and causing the evolution of slug mimicry in palatable ‘roly-polies’ that co-occur on the mudflat. These studies will provide new insight into how energy moves through the food-chain in estuaries, and how one species can have unexpected effects on many surrounding species in its ecosystem. We will also study how climate change has altered the distribution of slug species (and hence their compounds) along the U.S. west coast, which may have cascading but previously unrecognized effects on the inhabitants of threatened estuaries. Finally, the project will support the collaboration between two primary undergraduate institutions, one of which is Hispanic serving and a large research institution, via the collaboration between the three school many undergraduate and master’s students will be supported each year by the project. The project will focus on the recruitment of students historically underrepresented in science to the proposed research and outreach activities. We will test whether polyketide (PK) compounds produced by sea slugs function as keystone molecules, altering energy flow and community structure in Northern Hemisphere estuaries. Small sea slugs (Alderia) are exceptionally abundant (1000/m2) on mudflats, representing a potential resource for diverse fish, bird and invertebrate consumers. We will characterize a biosynthetic pathway and novel PK metabolites produced by slugs, and determine if PKs protect Alderia from wetland predators using a combination of laboratory and field assays with extracts and pure compounds. We will then estimate the net loss of primary production to higher trophic levels due to this chemical defense. The rapid evolution of Batesian mimicry in introduced isopods along the U.S. west coast will be assessed in this system to understand how chemical defense and visual predation affect phenotypic evolution of co-occuring organisms over short timescales. Manipulative experiments will test the effects of PKs on the microbiome and infaunal community of mudflats to determine the impact of shed compounds on diverse ecological processes in this sensitive nursery habitat. These studies will address, from gene to ecosystem, the impacts of potential keystone compounds synthesized as an antipredator defense in a common temperate mollusc. Modeling studies will explore the basis for range limits and the effects of ongoing climate change on shifting range boundaries between two Alderia species. These results will collectively provide new insight into how global change may alter the distribution of keystone molecules and thus have unanticipated effects on communities in already-threatened habitats such as estuaries.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.

河口是许多经济上重要的沿海物种对生态敏感的苗圃栖息地。一种潜在的重要但知识的食物资源，用于迁移的水鸟，少年鱼类和潜水的无脊椎动物捕食者是小海sl（alderia属），可以在整个北半球的温度泥泥中，每平方米超过1,000个slugs的密集聚集中发生。我们假设Alderia使用最近发现的新陈代谢分支来制作称为Polyketides的不良分子，该分子是一个包括医学上重要药物的化合物家族。我们将从这些丰富的slug中表征新的聚酮化合物，测试它们如何排斥捕食者，然后探索它们如何影响生态系统的许多其他方面。这些sl剂化合物的潜在影响包括通过抗生素作用改变泥浆中的细菌。驱除一些生活在泥泞中的动物，同时吸引其他动物。并导致在可口的“ roly-polies”中slug模仿的演变，并在泥flat上共同发生。这些研究将提供有关能量如何通过河口中的食物链移动的新见解，以及一个物种如何对其生态系统中许多周围物种产生意想不到的影响。我们还将研究气候变化如何改变了美国西海岸的sl剂物种的分布（以及它们的化合物），这可能对受威胁河口的居民有级联但以前无法识别的影响。最后，该项目将支持两个小学本科机构之间的合作，其中一家是西班牙裔服务和一家大型研究机构，这三所学校之间的合作将受到该项目的每年的支持。该项目将集中于招募科学中代表性不足的学生参加拟议的研究和外展活动。我们将测试由海sl子产生的聚酮化合物（PK）化合物是否起基石分子的作用，改变北半球河口的能量流和社区结构。小海sl（Alderia）在泥板上非常丰富（1000/m2），代表了潜在的鱼类，鸟类和无脊椎动物消费者的潜在资源。我们将表征由Slugs产生的生物合成途径和新型的PK代谢产物，并确定PKS是否使用实验室和野外暗杀以及提取物和纯化合物的混合物来保护Alderia免受湿地掠食者的影响。然后，由于这种化学防御，我们将估计初级产量的净损失为更高的营养水平。在该系统中，将评估Batesian模仿在美国西海岸引入的等异形体中的快速演变，以了解化学防御和视觉预览如何影响相互占领的生物体在短时间内的表型演化。操纵实验将测试PK对泥浆微生物组和iNfaunal社区的影响，以确定棚子化合物对这种敏感护理栖息地中潜水员生态过程的影响。这些研究将解决从基因到生态系统，在公共温度软体动物中合成为抗逆转器防御的潜在基石化合物的影响。建模研究将探索范围限制的基础以及持续的气候变化对两种alderia物种之间变化范围边界的影响。这些结果将共同提供有关全球变化如何改变基石分子的分布的新见解，因此对已经威胁性栖息地（例如河口）的社区产生了意外的影响。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子和更广泛影响的评估来通过评估来获得支持的珍贵的支​​持。