由于海洋吸收了大约30%的人为排放二氧化碳，打破了原本海洋中的碳酸盐化学平衡，进而导致了海水pH的降低，这种现象被称为海洋酸化（Ocean Acidification）。研究发现，海洋酸化能够对生物体的生长、发育、钙化、能量分配等生理过程产生显著影响（尤其钙化生物）；低氧也被证明能够干扰海洋生物的存活、行为方式以及机体的多种生理、生化过程。在自然条件下，海洋生态环境的变化是由多种因素综合作用的结果，海水酸化和低氧有时会同时发生。本研究以长牡蛎Crassostrea gigas为研究对象，整合利用蛋白质组学、代谢组学等技术，并结合传统生理学手段，分析了海水酸化以及海水酸化和低氧交互暴露后长牡蛎不同组织中的生理响应，研究结果可为准确预测海洋环境变化对贝类资源以及海洋生态系统的影响奠定基础，也可为国家制订相关应对策略与政策提供科学依据。 1. 长牡蛎稚贝对海水酸化响应的组学分析 采用核磁共振代谢组学与双向电泳蛋白质组学，分析了长牡蛎鳃、消化腺和外套膜组织对28天海水酸化暴露的响应。结果发现，海水酸化暴露导致长牡蛎鳃、消化腺和外套膜组织产生了能量代谢和渗透胁迫等多种生理响应。整合差异变化的代谢物和蛋白质，发现海水酸化能够影响鳃组织中四氢嘧啶的合成、牛磺酸代谢、甘油磷脂代谢以及三羧酸循环；在消化腺组织中，蛋白质降解、半乳糖代谢、牛磺酸代谢、半胱氨酸代谢以及三羧酸循环受到了影响；而在外套膜中，以三羧酸循环为代表的能量代谢过程、细胞纤维运动以及细胞骨架结构则发生了显著变化。 2. 长牡蛎对海水酸化及低氧交互暴露的响应 利用双向电泳蛋白质组学结合生理学手段，分析了长牡蛎鳃组织对海水酸化及低氧交互暴露的响应情况。结果显示，相比于对照组，低氧暴露可导致血细胞凋亡率和细胞吞噬率的显著上调，以及ROS含量的极显著下调，表明低氧暴露对长牡蛎的细胞免疫应答反应产生了严重的影响。双向电泳蛋白质组学分析发现，长牡蛎鳃组织对海水酸化及低氧交互暴露的生理响应既有相同点也有差异性。海水酸化暴露可能造成了鳃组织内氧化应激、信号传导和钙离子平衡方面的响应；低氧暴露则可能影响了鳃组织内的应激反应、信号传导和细胞骨架结构；海水酸化低氧交互暴露可能影响了鳃组织内的能量代谢、应激反应、钙离子平衡和蛋白质代谢等过程。 采用磷酸化蛋白质组学技术，分析了长牡蛎外套膜组织在海水酸化及低氧交互暴露后的响应情况。结果发现，在海水酸化及低氧交互暴露后，长牡蛎外套膜组织内参与能量代谢（AMP deaminase 2）、免疫反应（Cap1和Pcdc4）、信号传导（Cdc42）等生理过程的相关蛋白以及多种核糖体蛋白（如EG664969、Rps14和Rpsa等）和细胞骨架蛋白（如Pls3、Cap1和Cenpj等）的丰度发生了显著变化。整合差异表达蛋白发现，长牡蛎外套膜组织对海水酸化产生了MAPK信号通路和黏着连接等多个生理过程上的响应；低氧暴露则导致多个信号通路（Fc epsilon RI和T cell receptor信号通路等）的变化响应，进而可能影响到免疫应答和磷酸化调节过程；在酸化低氧交互暴露中，长牡蛎外套膜的神经内分泌调节系统（Ras和GnRH信号通路、多巴胺以及GABAergic的合成）受到了显著影响，进而可能导致组织功能的异常。

The gradually increased atmospheric CO2 partial pressure (pCO2) has thrown the carbonate chemistry off balance and resulted in decreased seawater pH in marine ecosystem, termed ocean acidification (OA). Anthropogenic OA is postulated to affect the physiological processes of many marine calcifying organisms, such as growth, development and calcification. Marine organisms were also found to respond to hypoxia with varied behavioral, physiological, and cellular responses. Despite the common co-occurrence of hypoxia and acidification in marine systems, their concurrent effects on ocean life are poorly understood. In this work, metabolomics, proteomics and traditionally physiological approaches were integrated to elucidate the effects of seawater acidification and/or hypoxia on Pacific oyster Crassostrea gigas, hopefully shedding light on the effects and mechanisms in a holistic and systematic mode. 1. Proteomic and metabolomic responses of Pacific oyster C. gigas to elevated pCO2 exposure NMR-based metabolomics and 2-DE-based proteomics were integrated to analyze the perturbance of elevated pCO2 in gills, hepatopancreas and mantles of C. gigas. It was found that seawater acidification could affect several physiological processes in C. gigas such as energy metabolism, osmotic stress and cytoskeleton structure. In gills, the alterations of proteins involved in ectoine biosynthesis, taurine metabolism, citrate cycle and glycerophospholipid metabolism were observed in response to elevated pCO2. In the tissue of hepatopancreas, the processes of protein degradation, galactose metabolism, taurine metabolism, cysteine metabolism and citrate cycle were altered. The alterations of citrate cycle and cytoskeleton structure were observed in mantle tissues. 2. Physiological responses of Pacific oyster C. gigas to elevated pCO2 and hypoxia exposure 2-DE-based proteomics and traditionally physiological approaches were applied to elucidate the perturbance of elevated pCO2 and/or hypoxia in C. gigas. Compared with the control group, hypoxia had a severely harmful effect on immune responses of C. gigas. In elevated pCO2 exposure treatment, the variation in abundances of proteins related to oxidative stress, signal transduction and Ca2+ homeostasis were identified. However, the alterations of proteins involved in stress response, signal transduction and cytoskeleton structure were observed under hypoxia exposure. When oysters were exposed to elevated pCO2 associated with hypoxia, proteins significantly altered in abundance were found to participate in the processes of energy metabolism, stress response, Ca2+ homeostasis and protein metabolism. Phosphoproteomic analysis was applied to elucidate the perturbance of elevated pCO2 and/or hypoxia in the mantle of C. gigas. The alterations of proteins involved in energy metabolism (AMP deaminase 2), immune response (Cap1 and Pcdc4), signal transduction (Cdc42), ribosomes (EG664969, Rps14 and Rpsa) and cytoskeleton (Pls3, Cap1 and Cenpj) were observed in mantle of oysters under elevated pCO2 and/or hypoxia exposure. Elevated pCO2 could affect a variety of biological processes, such as MAPK signal transduction and adherens junction. There were several signal transductors (such as Fc epsilon RI signal transduction and T cell receptor signal transduction) arousing in response to hypoxia, which perhaps led to changes in immune responses and regulation of phosphorylation. Elevated pCO2 associated with hypoxia exposure probably influenced the nervous system (Ras signal transduction, GnRH signal transduction, dopamine and GABAergic synthesis), which resulted in abnormal mantle tissue function.