Understanding the exceptional heat tolerance of reef corals from the Persian/Arabian Gulf

浅水珊瑚礁在全球范围内正在减少，预计将在本世纪内消失。热应力事件的频率和强度不断增加已被确定为对珊瑚礁生存的主要威胁。高温对珊瑚的影响可能因沿海海水污染等区域因素而加剧。在波斯湾/阿拉伯湾（下称“海湾”），珊瑚暴露在高盐度和不寻常的营养物浓度下。与此同时，他们忍受极端的温度最高，将杀死珊瑚在地球上的其他地方。尽管在定义珊瑚礁对热应力的敏感性的zooxanthropium的脂质成分的关键作用，具体的脂质特征的共生体的海湾珊瑚是尚未完全探索。拟议的研究将通过应用质谱（MS）方法来解决这一知识差距，以比较在极端温度栖息地（阿布扎比，阿联酋）蓬勃发展的海湾珊瑚虫的脂谱与在印度/南太平洋（霍加岛，斐济）经历典型热带条件的同类。我们将分析在一年中不同季节从两个现场采集的样本。与此同时，我们将监测同期理化环境的变化。这一战略将确定与珊瑚在高温下的生存和对环境条件变化的动态反应有关的虫黄藻的定量/定性脂质组成的关键差异。我们将使用我们建立的实验室菌株的Porites lobata源自海湾和太平洋，以研究如何改变温度，营养浓度和盐度分别影响的脂补充zooxanthropium。在受控条件下的实验将使我们能够测试我们的假设，即海湾独特的物理化学环境，通过改变虫黄藻的脂质组成，促进珊瑚的耐热性。该项目的比较方法将由参与科学家的高度互补的专门知识（珊瑚生理学/分子生物学/生物化学;脂质生物学/质谱分析和生物化学）来实现。该项目将受益于优秀的项目伙伴（Burt、Voolstra、Suggett、Smith）提供的大量实物捐助，以及来自学术界、工业界、关心海湾珊瑚生态系统的政府和非政府组织的利益攸关方组成的大型国际联合会的支持。

Shallow water coral reefs are on decline at a global scale and are expected to be lost within this century. The increasing frequency and intensity of heat stress episodes have been identified as the major threat to reefs survival. The impact of high temperature on corals can be exacerbated by regional factors such as pollution of coastal seawater. In the Persian/Arabian Gulf (hereafter: "the Gulf") corals are exposed to elevated salinity levels and unusual nutrient concentrations. At the same time, they endure extreme temperature maxima that would kill corals elsewhere on the planet. Despite the crucial role of the lipid composition of zooxanthellae in defining the susceptibility of reef corals to heat stress, the specific lipid signature characterising the symbionts of Gulf corals is as yet completely unexplored. The proposed study will address this knowledge gap by applying a mass spectrometric (MS) approach to compare the lipid profiles of zooxanthellae from Gulf corals flourishing in an extreme temperature habitat (Abu Dhabi, UAE) with those of conspecifics that experience typical tropical conditions in the Indo/South Pacific (Hoga Island, Fiji). We will analyse samples from the two field sites collected at different seasons over a year. In parallel, we will monitor changes in the physicochemical environment over the same period. This strategy will identify key differences in the quantitative / qualitative lipid composition of zooxanthellae associated with coral survival at high temperature and with the dynamic response to changes in environmental conditions. We will use our established laboratory strains of Porites lobata originating from the Gulf and the Pacific to examine how altered temperature, nutrient concentrations and salinity individually affect the lipid complement of zooxanthellae. The experiments under controlled conditions will allow us to test our hypothesis that the unique physicochemical environment of the Gulf promotes thermotolerance of corals by altering the lipid composition of zooxanthellae. The comparative approach of this project will be enabled by the highly complementary expertise of the participating scientists (coral physiology/molecular biology/biochemistry; lipid biology/mass spectrometry & biogeochemistry). The project will benefit from excellent project partners (Burt, Voolstra, Suggett, Smith) that provide substantial in-kind contributions and from the support of a large international consortium of stakeholders from academia, industry, governmental and non-governmental organizations concerned with the coral ecosystems of the Gulf.