CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; University of Chinese Academy of Sciences, Beijing 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China.
CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China.
J Proteomics. 2019 Feb 20;193:27-43. doi: 10.1016/j.jprot.2018.12.020. Epub 2018 Dec 21.
Multiple environmental stressors caused by global warming influence the regulation of proteins involved in various biological processes in aquatic organisms. As an important component of the marine ecosystem, sea cucumber is a suitable echinoderm species for researching stress responses. In this study, we have investigated the proteomic response of respiratory trees in the sea cucumber Apostichopus japonicus, challenged with environmental stresses by using the iTRAQ technique. Results showed that 262, 155 and 433 proteins were differentially regulated in response to heat, hypoxia, and heat plus hypoxia, respectively. Expression of key genes and proteins were measured by real-time PCR and western blot to validate the accuracy of the proteome files. Results showed that the interaction between these two stressors has an additive effect at the proteome level. Proteins involved in amino acid and carbohydrate metabolic processes were largely induced by heat while repressed by hypoxia. Exposure to multiple climate change stressors caused several proteins involved in lipid metabolic progress to be down-regulated and lipid catabolic processes were induced. Additionally, hypoxia and the combined stress induced proteins involved in iron homeostasis. ATP synthesis and gluconeogenesis were induced under heat and the combined stress, while ATP and glycogen synthesis were depressed under hypoxia. Proteins related with immune and defense response were largely induced and protein synthesis ability was depressed under all three stresses. Thus, sea cucumber may adopt different strategies to cope with varied environmental stress, and the situation in heat group is more similar with the combined treatment than hypoxia group. These proteomic changes in response to high-temperature and low-oxygen levels may provide insights into the defense strategies of sea cucumber in response to global climate changes. SIGNIFICANCE OF THE STUDY: The study focused on comparative quantitative proteomics on Apostichopus japonicus respiratory tree using iTRAQ in responses to multiple climate change stressors: heat, hypoxia and the combined stress. Data showed that A. japonicus can have an acute reaction in diverse biological pathways to both individual and interacting environmental stress, including substance metabolism, signal transduction, protein synthesis, immune response and energy production. Results indicated that sea cucumber adopted different strategies to cope with varied environmental stress, and the interaction between these two stressors has an additive effect at the proteome level. These results offer insight into the molecular regulation of A. japonicus to multiple environmental stress and reveal possible molecular events in sea cucumber under climate changes. The understanding of adaptive variation under global climate changes in aquatic organisms could be improved.
全球变暖导致的多种环境胁迫因素影响了水生生物中参与各种生物过程的蛋白质的调节。海参作为海洋生态系统的重要组成部分，是研究应激反应的合适棘皮动物物种。在这项研究中，我们使用 iTRAQ 技术研究了海参刺参呼吸树对环境胁迫的蛋白质组响应。结果表明，分别有 262、155 和 433 种蛋白质因热、缺氧和热加缺氧而差异调节。通过实时 PCR 和 Western blot 测量关键基因和蛋白质的表达，以验证蛋白质组文件的准确性。结果表明，这两种胁迫因素在蛋白质组水平上具有相加作用。参与氨基酸和碳水化合物代谢过程的蛋白质在热刺激下大量诱导，而在缺氧时受到抑制。暴露于多种气候变化胁迫下，导致几种参与脂质代谢过程的蛋白质下调，并诱导脂质分解代谢。此外，缺氧和联合胁迫诱导铁稳态相关蛋白。在热和联合胁迫下诱导 ATP 合成和糖异生，而在缺氧下抑制 ATP 和糖原合成。在三种胁迫下，与免疫和防御反应相关的蛋白质大量诱导，蛋白质合成能力受到抑制。因此，海参可能采用不同的策略来应对不同的环境胁迫，并且在热组中与联合处理的情况更相似，而不是与缺氧组相似。这些对高温和低氧水平的蛋白质组变化可能为海参应对全球气候变化的防御策略提供了一些见解。
本研究重点是使用 iTRAQ 对海参呼吸树进行多重气候变化胁迫（热、缺氧和联合胁迫）的比较定量蛋白质组学研究。数据显示，海参可以在各种生物途径中对单个和相互作用的环境胁迫产生急性反应，包括物质代谢、信号转导、蛋白质合成、免疫反应和能量产生。结果表明，海参采用不同的策略来应对不同的环境胁迫，并且这两种胁迫因素在蛋白质组水平上具有相加作用。这些结果为海参对多种环境胁迫的分子调控提供了见解，并揭示了气候变化下海参可能的分子事件。可以提高对水生生物在全球气候变化下适应变化的理解。
