RAPID: Collaborative Research: Disentangling the effects of heat stress versus bleaching phenotype on coral performance

RAPID：合作研究：解开热应激与白化表型对珊瑚性能的影响

• 批准号: 2102989
• 负责人: Katie Barott
• 金额: $ 1.45万
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-12-15 至 2022-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2102989&HistoricalAwards=false
• 关键词: RAPID; Collaborative; Research; Disentangling; effects

Coral bleaching has become increasingly common on reefs worldwide as rising sea surface temperatures associated with climate change disrupt the coral-algal symbiosis. This dramatic heat stress response turns the normally colorful corals bright white, and yet during these heat stress events not all corals undergo bleaching. This project focuses on assessing the effects of bleaching by comparing pairs of corals side-byside on the reef during an ongoing heat wave, where one has bleached and the other has not, despite experiencing the same temperatures. These coral pairs have been monitored throughout three bleaching events in the past five years, providing a unique resource to address whether corals with consistently different bleaching susceptibilities have the capacity to acclimate in response to disturbances throughepigenetic changes, or changes in gene expression not due to change in DNA bases. To address this, the project will characterize the impacts of bleaching or not bleaching on coral physiology, gene expression, and epigenetic patterns using coral pairs in their natural habitat during a marine heatwave. This project also provides research support for graduate student trainees, as well as data and materials for the research and training of undergraduate and high school students. This project will recruit underrepresented minority students from URI and UPenn area high schools and university undergraduates for work on computer analysis of images (benthic and colony photographs, brightfield and confocal micrographs) and sequencing data. It will also support the training of an undergraduate student at the University of Hawaiʻi in coral ecology and physiology, and the development of her senior thesis.This project will investigate the effects of repeated heat stress events on the performance of Montipora capitata, a dominant reef builder throughout Hawaiʻi. It utilizes the timely context of paired colonies of M. capitata with bleached vs. unbleached histories that have been monitored through two past bleaching events in Hawaiʻi (2015 and 2019) and the currently ongoing 2020 event. This system allows for the unique opportunity to disentangle the consequences of heat stress versus bleaching on coral performance through time, an essential feature of reef resilience. The contrasting physiological and energetic processes these two phenotypes undergo during a heatwave are likely to result in alterations to the cellular environment within the animal that impacts epigenetic transcriptional regulation. These regulatory and energetic changes, if persistent over time, have the potential to alter coral fitness beyond the duration of the heatwave differentially between corals with contrasting bleaching phenotypes. Specifically, the project will: 1) quantify the effect of the 2020 heatwave on coral physiology during bleaching and recovery, 2) generate a corresponding archive of coral tissues and nucleic acids as a resource for future work characterizing how bleaching phenotype alters energetics and non-genetic inheritance, and 3) characterize how bleaching phenotype alters intra-generational inheritance of epigenetic marks (i.e., DNA methylation) and gene expression, and the duration of these marks and expression patterns following heat stress. This project represents an urgent assessment of an ideal system to test the legacy of coral bleaching phenotype on coral fitness. The results of this project will therefore lay the foundation for intra and cross-generational effects of bleaching vs. heat stress, which is essential for understanding coral resilience to climate change.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.

由于气候变化导致海面温度上升，破坏了珊瑚与藻类的共生关系，珊瑚白化现象在世界范围内的珊瑚礁上变得越来越普遍。这种剧烈的热应激反应使通常色彩缤纷的珊瑚变成亮白色，但在这些热应激事件期间，并非所有珊瑚都会发生白化。该项目的重点是通过比较在持续的热浪期间珊瑚礁上并排的珊瑚对白化的影响，其中一个已经白化，另一个没有，尽管这些珊瑚对经历了相同的温度。三起白化事件在过去五年中，该项目提供了独特的资源，以持续解决具有不同白化敏感性的珊瑚是否有能力通过表观遗传变化或非 DNA 碱基变化引起的基因表达变化来适应干扰。将利用海洋热浪期间自然栖息地的珊瑚对来描述白化或不白化对珊瑚生理学、基因表达和表观遗传模式的影响。该项目还为研究生学员提供研究支持，并提供数据和材料。该项目将招募来自 URI 和宾夕法尼亚大学地区高中的少数族裔学生和大学本科生，从事图像（底栖动物和群体照片、明场和共焦显微照片）和测序数据的计算机分析工作。它还将支持夏威夷大学一名本科生在珊瑚生态学和生理学方面的培训，以及她的高级论文的发展。该项目将研究重复的热应激事件对珊瑚表现的影响。 Montipora capata 是整个夏威夷的主要珊瑚礁建造者，它利用了 M.capitalata 配对群体的及时背景，以及通过夏威夷过去的两次白化事件（2015 年和 2019 年）和当前正在进行的 2020 年事件进行监测的漂白与未漂白历史。该系统提供了独特的机会来解开热应激与白化对珊瑚性能随时间的影响，这是珊瑚礁恢复能力的一个基本特征。这两种表型在热浪期间经历的能量过程可能会导致动物体内细胞环境的改变，从而影响表观遗传转录调控。这些调节和能量变化如果持续一段时间，就有可能改变珊瑚的适应性。具体而言，该项目将：1）量化 2020 年热浪对珊瑚白化和恢复期间生理的影响，2）生成相应的珊瑚组织和核酸档案。未来工作的资源，描述漂白表型如何改变能量学和非遗传遗传，3) 描述漂白表型如何改变表观遗传标记（即 DNA 甲基化）和基因表达的代内遗传，以及这些标记和表达的持续时间该项目代表了对理想系统的紧急评估，以测试珊瑚白化表型对珊瑚健康的影响，因此该项目的结果将为白化与热应激的代内和跨代影响奠定基础。 ,这对于了解珊瑚对气候变化的适应能力至关重要。该奖项反映了 NSF 的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。