Collaborative Research: Cell biology of cnidarian-dinoflagellate symbiosis: Signaling, regulation and host response pathways

珊瑚礁生态系统是生物多样性的温床，为全球5亿人提供宝贵的环境和经济服务，其中包括数百万美国人。除非人类能够控制全球气温上升，否则到本世纪末，由于全球变暖，珊瑚礁将面临几乎完全的破坏。珊瑚生物学家正在共同努力，制定一系列广泛的解决方案，以帮助应对珊瑚礁危机。作为这些努力的一部分，发现起着至关重要的作用。珊瑚是珊瑚动物与数百万居住在珊瑚细胞内的单细胞藻类之间的亲密共生关系。藻类为寄主提供光合作用衍生的糖，以换取营养和栖息地。全球变暖和其他人为影响造成的共生功能失调，是珊瑚白化的驱动因素，正在造成全球范围内广泛的珊瑚礁退化。该奖项将研究控制珊瑚-藻类伙伴关系的细胞和分子机制。研究人员将使用最先进的细胞和分子工具来发现伴侣之间交换的化学信号。他们将描述藻类在寄主早期发育中的作用，并探索健康共生和漂白过程中伙伴间调节的机制。该奖项包括广泛的教育和推广目标。本科生、研究生和博士后的培养是这项工作的核心。最后，研究人员将通过各种活动直接与俄勒冈州和佛罗里达州的公众接触，旨在说明珊瑚对科学和社会的重要性。许多刺胞动物，包括珊瑚和海葵，与光合鞭毛藻（共生鞭毛藻科）共生，共同构成珊瑚礁生态系统的营养和结构基础。尽管珊瑚对珊瑚礁很重要，而且在气候变化时代，珊瑚礁的健康状况受到威胁，但我们对如何建立、管理和维持伙伴关系的了解并不完全。研究人员将研究刺胞-鞭毛藻共生的发生、维持和破坏过程中伴侣间的信号和调节。实验将主要在以实验室为基础的海葵-共生体科模型系统中进行。该团队将开展以下具体目标：目标1：通过不同共生体物种的分子聚糖分析和使用无偏DNA适体技术识别共生藻类的表面决定因素，表征共生开始、维持和破裂期间藻类-宿主信号动力学。目的2：通过研究共生体在水螅体发育中的作用，探索水螅体发育过程中共生体入侵的动态，描述寄主体内共生体的时空格局及其对寄主发育生长的影响。目的3：通过测量宿主组织中NADPH氧化酶活性和鞘氨醇变阻器信号在共生开始和生态失调期间的变化，研究宿主反应途径在共生调节中的作用。研究人员将开发一个基于海葵-共生科模式系统的基于课程的本科生研究经验（CURE），他们将研究CURE在学生学习和建立科学身份方面的有效性。该奖项反映了美国国家科学基金会的法定使命，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。

Coral reef ecosystems are biodiversity hotbeds that provide valuable environmental and economic services to half a billion people globally, including millions in the US. Reefs are faced with almost complete destruction by the end of the century due to global warming unless humanity can cap global temperature rise. Coral biologists are working together to develop a broad array of solutions to help with the coral reef crisis. As a part of these efforts, discovery has a critical role to play. Corals are an intimate symbiosis between the coral animal and millions of single-celled algae that reside inside of coral cells. The algae provide photosynthetically derived sugars to the host in return for nutrients and a habitat. Dysfunction of the symbiosis, caused by global warming and other human-caused impacts, is the driver of coral bleaching and is causing widespread reef degradation globally. This award will examine the cellular and molecular mechanisms governing the coral-algal partnership. The researchers will use state-of-the-art cellular and molecular tools to discover the chemical signals exchanged between the partners. They will describe the role of the algae in early development of the host and explore the mechanisms of inter-partner regulation during healthy symbiosis and bleaching. The award includes extensive education and outreach aims. Undergraduate, graduate student and postdoctoral fellow training is central to the work. Finally, the researchers will engage directly with the public, both in Oregon and Florida, through a variety of activities aimed at illustrating the importance of corals to science and society.Many cnidarians, including corals and anemones, engage in a symbiosis with photosynthetic dinoflagellates (family Symbiodiniaceae) that together form the trophic and structural foundation of the coral reef ecosystem. Despite the importance of corals to coral reefs and the threatened state of coral reef health in an era of climate change, we have an incomplete understanding of how the partnerships are established, regulated and maintained. The researchers will examine inter-partner signaling and regulation during onset, maintenance and breakdown of cnidarian-dinoflagellate symbioses. Experiments will be conducted largely in a laboratory-based sea anemone-Symbiodiniaceae model system. The team will carry out the following Specific Aims: Aim 1: Characterize algal-host signaling dynamics during onset, maintenance and breakdown of symbiosis by molecular glycan profiling of different symbiont species and by using a unbiased DNA aptamer technique to identify surface determinants of symbiotic algae. Aim 2: Describe the spatio-temporal patterning of symbionts in hosts and their impact on host development and growth by examining the role of symbiosis on polyp development and exploring the dynamics of symbiont invasion in developing polyps. Aim 3: Examine the role of host response pathways in regulation of symbiosis by measuring changes in NADPH oxidase activity and sphingosine rheostat signaling in host tissues both during onset of symbiosis and in dysbiosis. The researchers will develop a course-based undergraduate research experience (CURE) based on the sea anemone-Symbiodiniaceae model system and they will examine the effectiveness of the CURE in student learning and in building of science identity.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.