Collaborative Research: Ecological Genomics of Stress Response in an Intertidal Copepod

海洋生物学研究的一个主要目标是根据生物对环境的适应来了解生物的分布和丰度。这种理解对于预测环境变化将如何改变海洋生产力和生态系统服务至关重要。对极端物理条件的耐受性在决定物种分布方面起着重要作用。虽然许多海洋动物的生理耐受性已经得到了很好的研究，但这些耐受性在多大程度上可以通过进化变化来调节，仍然基本上是未知的。因此，我们通常了解个体生物如何应对环境压力，但对物种内部现有的遗传变异是否允许对全球变暖或海洋酸化等压力源做出快速进化反应知之甚少。桡足类是小型甲壳类动物，是地球上数量最多的动物之一，也是海洋和淡水食物网的关键组成部分。尽管它们具有重要的生态意义，但只有有限的遗传数据可用于任何桡足类物种。为了了解这些生物如何在长时间和短时间内适应环境的变化，该项目将重点获取潮汐池桡足动物加利福尼亚虎足的基因组序列，然后将利用这些基因组信息来了解该物种如何应对环境变化。这项研究有三个主要的科学组成部分。首先，将对四个地理上孤立的种群进行基因组测序，以便比较全基因组范围内的种群差异。将选择目标种群，以提供种群对两种关键环境胁迫，热胁迫和盐度胁迫的反应对比。第二个组成部分将是检查哪些基因对这些环境压力作出反应，以帮助确定用于在这两种压力下生存的机制。最后，第三个组成部分将使用实验室杂交和遗传作图方法来研究基因组的哪些区域赋予对盐度和温度胁迫的耐受性。通过整合这三个方面，这项研究将深入了解这个物种（可能还有其他生物）如何应对基本的环境压力。在更广泛的层面上，解码完整的桡足动物基因组将为了解这一生态重要群体的其他物种的基本生物学提供关键资源，序列数据可通过标准数据库和新开发的网站（http://sio.ucsd.edu/Research/copepod_genomics/）获得。这个项目包括广泛的推广，并将通过为小学生提供的项目和为公共水族馆的游客提供的展览，向公众展示现代海洋科学是如何进行的。推广工作还将扩展到更广泛的海洋科学界，以帮助展示如何利用基因组学来研究传统上没有利用遗传技术的海洋系统中的基本问题。最后，这项研究将在海洋科学、生理学和基因组学这一令人兴奋的结合领域直接培养一批年轻科学家。

A major goal of marine biological research is to understand the distribution and abundance of organisms in light of their adaptations to the environment. Such an understanding is critical to predicting how environmental changes will alter oceanic productivity and ecosystem services. Tolerance of physical extremes plays a major role in determining species distributions. Although the physiological tolerances of many marine animals have been well studied, the extent to which these tolerances can be adjusted by evolutionary change remains essentially unknown. Consequently, we often have knowledge of how individual organisms respond to environmental stresses but little understanding of whether existing genetic variation within species will permit rapid evolutionary responses to stressors such as global warming or ocean acidification.Copepods are small crustaceans that are among the most numerous animals on the planet and are key components of marine and freshwater food webs. Despite their ecological importance, only limited genetic data are available for any copepod species. In order to understand how these organisms can adapt to changes in their environment over both long and short time periods, this project will focus on obtaining genome sequences for the tidepool copepod, Tigriopus californicus, and then will use this genomic information to understand how the species responds to environmental change. The study has three major scientific components. First, the genome will be sequenced from four geographically isolated populations to allow comparison of genome-wide population differences. Target populations will be selected to provide contrasts in population responses to two key environmental stresses, thermal stress and salinity stress. The second component will be to examine which genes respond to these environmental stresses to help determine the mechanisms used to survive these two stresses. Finally, the third component will use laboratory crosses and genetic mapping approaches to look at what regions of the genome confer tolerance to salinity and temperature stress. By integrating across all three aspects, this study will yield insights into how this species (and likely other organisms) respond to basic environmental stresses.At a broader level, the decoding of a complete copepod genome will provide a key resource for understanding the basic biology of other species of this ecologically important group, with sequence data made available through standard databases and a newly-developed website (http://sio.ucsd.edu/Research/copepod_genomics/). This project includes extensive outreach and will bring a public window into how modern marine science is conducted through programs for elementary school children and exhibits for visitors to public aquaria. Outreach will also be extended to the broader marine sciences community to help show how genomics can be used to study fundamental questions in marine systems that traditionally have not utilized genetic techniques. Finally, the research will directly train a number of young scientists in this exciting combination of marine science, physiology, and genomics.