NSFDEB-NERC The blueprint for marine biomineralization in a changing climate

NSFDEB-NERC 气候变化下海洋生物矿化的蓝图

• 批准号: NE/W005115/1
• 负责人: Clare Bird
• 金额: $ 72.18万
• 依托单位: University of Stirling
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FW005115%2F1
• 关键词: NSFDEB; NERC; blueprint; marine; biomineralization

Understanding and quantifying the global carbon cycle (interchange of carbon between atmosphere, ocean, and land) is essential for predicting future concentrations of atmospheric carbon dioxide (CO2), which is responsible for about two thirds of global warming. The ocean absorbs over a third of the CO2 that enters the atmosphere by natural and human activity. As the concentration of atmospheric CO2 increases therefore, so does the concentration of CO2 dissolved in our oceans. This makes our oceans progressively less alkaline, in a process termed ocean acidification (OA). OA has serious consequences, particularly for those marine organisms that make calcium carbonate (calcite) shells (e.g., mussels and oysters) or structures (e.g., corals), because calcite dissolves in more acidic environments.Some of the most globally important marine calcifying organisms affected by OA are microscopic single-celled animals called foraminifera. Foraminifera are widely distributed in marine systems and provide a major route for the removal of CO2 from the atmosphere through the long-term, deep-sea burial of their calcite shells. How ongoing ocean acidification and warming will affect the rate of foraminiferal calcification and calcite burial in coming decades, however, is currently poorly understood. This is largely because we do not understand how foraminifera calcify and how they will respond to future OA and ocean warming. As a result, it is not possible to confidently predict how climate change will impact the future carbon cycle and atmospheric CO2 concentrations.This project will be the first ever to investigate the molecular mechanism that foraminifera use to build their shell, to discover how they calcify. The initiation of calcification in foraminifera occurs on a highly specialised organic membrane that forms a "bubble" on which the new shell layer is crystalized. We know that the proteins in the organic membrane are responsible for this process but not specifically which of the proteins present are responsible for calcite nucleation, or the environmental conditions required for this to occur. Our project has three major objectives. The first is to identify the organic membrane proteins by sequencing both the proteins and the genome (the complete set of DNA in the cell) of two model species of foraminifera. The second objective is to identify which of the organic membrane proteins are key in calcite nucleation and the third objective is to discover how these proteins behave under different environmental conditions. Fulfilling our objectives will enable us for the first time to identify the critical genes and proteins that drive calcification in the foraminifera, and their response to ocean acidification. This exciting project will provide biologists with the first complete set of gene sequences (the genome) of the foraminifera, which provides all the information they require to function. The availability of genomes is a fundamental requirement for the study of any organism and will significantly improve and increase the kinds of studies that can be carried out, substantially advancing our understanding of foraminiferal biology. These genomes will be publicly available via continued open access in online databases for the advancement of research. Discovering the proteins responsible for calcification and how they are controlled and respond to environmental changes will above all, enable us to assess foraminiferal susceptibility to climate change in the future. It will equip scientists with the capability to more confidently predict how climate change will impact the future carbon cycle and atmospheric CO2 concentrations.

理解和量化全球碳循环（大气，海洋和土地之间的碳的互换）对于预测未来大气二氧化碳（CO2）的浓度至关重要，二氧化碳（CO2）造成了大约三分之二的全球变暖。海洋在三分之一的二氧化碳中吸收，通过自然和人类活动进入大气。因此，随着大气二氧化碳的浓度的增加，二氧化碳浓度也溶解在我们的海洋中。这使我们的海洋在称为海洋酸化的过程（OA）中逐渐降低了碱性。 OA有严重的后果，特别是对于那些使碳酸钙（方解石）贝壳（例如贻贝和牡蛎）或结构（例如珊瑚）（例如珊瑚）的海洋生物，因为方解石溶解在更酸性的环境中。一种在全球范围内最重要的海洋钙化有机体受OA影响的海洋生物，是由OA产生的微观单镜单一动物，称为单核动物。有孔虫被广泛分布在海洋系统中，并通过长期，深海埋葬的方解石壳从大气中去除二氧化碳。然而，目前了解到，持续的海洋酸化和变暖将如何影响有孔虫钙化和方解石埋葬的速率。这主要是因为我们不了解有孔虫如何钙化以及它们如何应对未来的OA和海洋变暖。结果，不可能自信地预测气候变化将如何影响未来的碳循环和大气二氧化碳浓度。该项目将是有史以来第一个研究有孔虫用于建造其壳的分子机制，以发现它们的钙化方式。在有孔虫中钙化的启动发生在高度专业的有机膜上，该膜形成了一种“气泡”，新的壳层在该膜上被晶体结晶。我们知道，有机膜中的蛋白质是造成此过程的原因，但并非具体构成了哪种蛋白质负责方解石成核或发生这种情况所需的环境条件。我们的项目有三个主要目标。首先是通过对两个有孔虫模型物种的蛋白质和基因组（细胞中的DNA的完整集）进行测序来鉴定有机膜蛋白。第二个目标是确定哪种有机膜蛋白是方解石成核中的关键，第三个目标是发现这些蛋白在不同的环境条件下的作用。实现我们的目标将使我们首次能够确定驱动有孔虫中钙化的关键基因和蛋白质及其对海洋酸化的反应。这个令人兴奋的项目将为生物学家提供有孔虫的第一组基因序列（基因组），该基因序列（基因组）提供了它们功能所需的所有信息。基因组的可用性是对任何生物体研究的基本要求，并且将显着改善并增加可以进行的研究的种类，从而实质上促进了我们对有孔虫生物学的理解。这些基因组将通过在线数据库中的持续开放访问公开获得，以促进研究的发展。发现负责钙化的蛋白质及其如何控制以及对环境变化的反应将最重要的是，使我们能够评估未来气候变化的有孔虫敏感性。它将使科学家能够更自信地预测气候变化将如何影响未来的碳循环和大气二氧化碳浓度。