Collaborative Research: Molecular profiling of the ecophysiology of dormancy induction in calanid copepods of the Northern Gulf of Alaska LTER site

亚北极太平洋维持着主要的渔业，几乎所有商业上重要的物种都直接或间接依赖于富含脂质的桡足类（新哲水蚤、新哲水蚤、新哲水蚤和哲水蚤）。 反过来，这些物种依赖于短暂的春季藻类生长和脂质储存的积累，以完成包括休眠期的年度生命周期。这个项目的智力推力测量藻华的时间和规模如何影响准备休眠使用现场和实验观察相结合。阿拉斯加的北方海湾-有四种哲水蚤物种经历休眠，陡峭的环境梯度，良好的浮游植物水华动态，并同时NSF-LTER程序-提供了一个不寻常的机会，以确定影响休眠准备的因素。教育和推广计划与研究相结合。教育工作的重点是为本科生、研究生和博士后学员提供跨学科的机会。该项目将为现有的研究生和本科生课程提供内容。联合阿拉斯加费尔班克斯和美国马诺阿的夏威夷是阿拉斯加土著和夏威夷土著服务机构，将招募这些团体的学生参加该项目。 由于渔业是阿拉斯加湾的主要产业，外联活动将利用与生产周期相关的动态食物网概念，宣传桡足类在海洋生态系统中的作用。桡足类的滞育（休眠）和伴随的脂质积累已被确定为高纬度生态系统的关键驱动因素，这些生态系统支持经济上重要的渔业，包括阿拉斯加湾的渔业。 虽然富含脂质的桡足类的消失与鱼类资源的严重减少有关，但人们对成功完成桡足类生命周期所需的环境条件知之甚少。 测量相对基因表达的生理分析方法将用于测试两个备选假设：脂质积累窗口假设，认为个体只有在积累了足够的脂质储存后才进入滞育，以及发育程序假设，认为一旦滞育程序被激活，进展独立于脂质积累。 具体目标是：1）确定食物水平对N。利用多种生理和发育标记对flemingeri桡足类向滞育进展的阶段进行了研究; flemingeri跨越环境梯度和跨越年份; 3）比较共存的哲水蚤物种（N. flemingeri、新哲水蚤Neocalanus plumchrus、新哲水蚤Neocalanus cristatus和哲水蚤Calanus marshallae）; flemingeri。 更广泛的科学意义包括获取新的基因组数据和分子资源，这些数据将通过已建立的数据库公开提供，以及开发用于常规获取桡足类生理概况的新工具。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。

The sub-arctic Pacific sustains major fisheries with nearly all commercially important species depending either directly or indirectly on lipid-rich copepods (Neocalanus flemingeri, Neocalanus plumchrus, Neocalanus cristatus and Calanus marshallae). In turn, these species depend on a short-lived spring algal bloom for growth and the accumulation of lipid stores in order to complete an annual life cycle that includes a period of dormancy. The intellectual thrust of this project measures how the timing and magnitude of algal blooms affect preparation for dormancy using a combination of field and experimental observations. The Northern Gulf of Alaska - with four calanid species that experience dormancy, steep environmental gradients, well-described phytoplankton bloom dynamics, and a concurrent NSF-LTER program - provides an unusual opportunity to identify the factors that affect dormancy preparation. Education and outreach plans are integrated with the research. Educational efforts focus on interdisciplinary opportunities for undergraduate, graduate and post-doctoral trainees. The project will generate content for existing graduate and undergraduate courses. U. of Alaska Fairbanks and U. Hawaii at Manoa are Alaska Native and Native Hawaiian Serving Institutions, and students from these groups will be recruited to participate in the project. Because fishing is a major industry in the Gulf of Alaska, outreach will communicate the role copepods play in marine ecosystems using the concept of a dynamic food web tied to production cycles.Diapause (dormancy) and the accompanying accumulation of lipids in copepods have been identified as key drivers in high latitude ecosystems that support economically important fisheries, including those of the Gulf of Alaska. While the disappearance of lipid-rich copepods has been linked to severe declines in fish stocks, little is known about the environmental conditions that are required for the successful completion of the copepod's life cycle. A physiological profiling approach that measures relative gene expression will be used to test two alternative hypotheses: the lipid accumulation window hypothesis, which holds that individuals enter diapause only after they have accumulated sufficient lipid stores, and the developmental program hypothesis, which holds that once the diapause program is activated, progression occurs independent of lipid accumulation. The specific objectives are: 1) determine the effect of food levels during N. flemingeri copepodite stages on progression towards diapause using multiple physiological and developmental markers; 2) characterize the seasonal changes in the physiological profile of N. flemingeri across environmental gradients and across years; 3) compare physiological profiles across co-occurring calanid species (N. flemingeri, Neocalanus plumchrus, Neocalanus cristatus and Calanus marshallae); and 4) estimate the reproductive potential of the overwintering populations of N. flemingeri. The broader scientific significance includes the acquisition of new genomic data and molecular resources that will be made publicly available through established data repositories, and the development of new tools for routinely obtaining physiological profiles of copepods.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.