OCE-PRF: Effects of increasing temperature and ultraviolet radiation on copepod mitochondria along a latitudinal gradient

该奖项的全部或部分资金来自《2021年美国救援计划法案》(公法117-2)。我们对生物应对气候变化的机制的了解还不完全。随着温度和紫外线(UV)辐射的增加，生物生存和繁殖的能力取决于它们适应环境变化的能力。线粒体在动物体内产生能量的能力受到这些细胞器的运动(即行为)和结构的影响。线粒体产生能量的能力直接影响动物的表现，包括生存和繁殖。反过来，线粒体的行为和结构又受到环境的影响。这项工作的目的是：1)确定紫外线辐射是否以实验室环境中观察到的相同方式影响海洋生物--桡足类自然种群中的线粒体行为和结构；2)确定温度是否影响桡足类自然种群中的线粒体行为和结构；以及3)确定线粒体的行为和结构在多大程度上因环境条件的变化而在短期和长期内发生变化。这项研究的结果将改变我们对桡足类等对环境重要的生物如何应对气候变化的理解。与奥本大学科学和数学学院合作，这项工作将促进阿拉巴马州学生的教育和科学素养。PI将开发几个外联计划，以适应奥本大学现有的基础设施，以增加1-6年级和11-12年级学生的科学参与度和识字率，并与社区互动，讨论研究对普通公众的重要性和相关性。这些外展活动将让学生亲身参与学习科学过程、线粒体、桡足类动物以及在科学研究中使用显微镜。公众将深入了解这项研究在了解气候变化对我们世界上最丰富的水生生物之一的影响方面的重要性。这项工作的目标是将观测野外工作和实验实验室工作结合起来，以进一步了解环境应激源对北美西海岸桡足类生理生态的影响。这项工作旨在从根本上改变我们对桡足类等普遍存在的浮游动物可能对气候变化做出反应的机制的理解。PI将从加利福尼亚州圣地亚哥、俄勒冈州巴特罗克和华盛顿州星期五港的种群中收集桡足类动物的数据。他将在白天紫外线暴露最高和温度最高的时候测量它们的代谢率，在晚上测量紫外线暴露和温度最低时的代谢率。在测量代谢率后，固定相同的桡足类动物，进行透射电子显微镜(TEM)定量观察线粒体的行为和形态，包括线粒体内膜的密度、线粒体间连接的比例、线粒体密度以及线粒体面积和长径比。来自这些种群的额外的桡足类动物将被运往奥本大学，以便在与野外测量的温度和紫外线辐射相同的情况下建立实验室种群。通过电子显微镜量化的线粒体表型和代谢率将在实验室进行相互移植实验后进行测量，以确定线粒体表型的差异是由于环境差异还是进化的、对温度和紫外线辐射反应的遗传差异。在与俄勒冈州立大学的合作下，将在移植实验中完成转录转录，以确定可能与线粒体行为和形态相关的基因的上调/下调，以保持三个群体之间的代谢率不同。桡足类是水生生态系统生物多样性的基石。因此，我们必须开始了解这些生物的生理反应，以便我们可以更好地了解气候变化对海洋种群的影响。这一奖项反映了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。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).Our understanding of the mechanisms by which organisms respond to climate change is incomplete. As temperature and ultraviolet (UV) radiation increase, the ability of organisms to survive and reproduce depends on their ability to adapt to changes in the environment. The ability of mitochondria to produce energy in animals is influenced by the movements (i.e., behavior) and structure of these organelles. The ability of mitochondria to produce energy directly impacts animal performance, including survival and reproduction. In turn, the behavior and structure of mitochondria are influenced by the environment. This work aims to: 1) determine if UV radiation influences mitochondrial behavior and structure in natural populations of a marine organism, copepods, in the same manner observed in a laboratory setting, 2) determine if temperature affects mitochondrial behavior and structure in natural populations of copepods, and 3) determine how much the behavior and structure of mitochondria change in the short-term versus the long-term in response to changing environmental conditions. The results of this study will transform our understanding of how environmentally important organisms such as copepods may respond to climate change. In collaboration with the Auburn University College of Science and Mathematics, this work will advance the education and science literacy of students in the state of Alabama. The PI will develop several outreach programs to fit the pre-existing infrastructure at Auburn University to increase the science involvement and literacy for 1st – 6th and 11th – 12th grade students and interact with the community to discuss the importance and relevance of the research for the general public. These outreach initiatives will involve hands-on participation of students in learning about the scientific process, mitochondria, copepods, and the use of microscopes in scientific research. The general public will gain insight into the importance of the research in understanding the impact of climate change on one of our world’s most abundant aquatic organisms. The goal of this work is to integrate observational fieldwork and experimental lab work to further understand the impact of environmental stressors on the physiological ecology of copepods along the west coast of North America. This work aims to fundamentally change our understanding of the mechanisms by which pervasive zooplankton such as copepods can potentially respond to climate change. The PI will collect data on copepods from populations in San Diego, CA, Battle Rock, OR, and Friday Harbor, WA. He will measure their metabolic rate at the point of highest UV exposure and temperature during the day and lowest UV exposure and temperature at night. After measuring metabolic rate, the same copepods will be fixed for transmission electron microscopy (TEM) to quantify mitochondrial behavior and morphology, including density of the inner mitochondrial membrane, proportion of inter-mitochondrial junctions, mitochondrial density, and mitochondrial area and aspect ratio. Additional copepods from these populations will be shipped to Auburn University to establish lab populations under the same temperatures and UV radiation as measured in the field. Mitochondrial phenotypes quantified via TEM and metabolic rate will be measured following reciprocal transplant experiments in the lab to determine the extent that differences in mitochondrial phenotype are due to environmental variation versus evolved, genetic differences in response to temperature and UV radiation. In collaboration with Oregon State University, transcriptomics will be completed under the transplant experiments to identify the up/downregulation of genes that may be associated with mitochondrial behavior and morphology to maintain metabolic rate differently between the three populations. Copepods are a cornerstone of biological diversity in aquatic ecosystems. As such, it is imperative that we begin to understand the physiological responses of these organisms so that we may better understand the impact of climate change on marine populations.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.