Cheng Chang-Hong, Liao Min-Ze, Ma Hong-Ling, Liu Guang-Xin, Fan Si-Gang, Deng Yi-Qin, Jiang Jian-Jun, Feng Juan, Guo Zhi-Xun
Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences / Southern Marne Science and Engineering Guangdong Laboratory (Zhuhai), Guangzhou, 510300, China; Sanya Tropical Fisheries Research Institute, China.
Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences / Southern Marne Science and Engineering Guangdong Laboratory (Zhuhai), Guangzhou, 510300, China.
Mar Environ Res. 2026 Mar 10;217:107978. doi: 10.1016/j.marenvres.2026.107978.
Salinity is a critical abiotic factor regulating the physiological homeostasis of aquatic crustaceans. To elucidate the physiological and molecular mechanisms underlying the adaptation of the mud crab Scylla paramamosain (Estampador, 1950) to low salinity, individuals were exposed to low salinity (3‰) and control (28‰) conditions for 7 days. Physiological assays revealed that low salinity stress induced significant oxidative stress and tissue damage in the hepatopancreas, characterized by significantly increased activities of SOD (increased by 32.27%), CAT (increased by 56.23%), T-AOC (increased by 152.68%), and AST (increased by 24.77%). Transcriptomic analysis identified 489 differentially expressed genes (DEGs), comprising 268 up-regulated and 221 down-regulated genes. Functional enrichment analysis demonstrated that mud crab acclimates to the hypotonic environment by enhancing transmembrane ion transport and synchronously activating "Arginine and proline metabolism" to modulate intracellular organic osmolytes. Concurrently, the significant activation of the p53 signaling pathway suggests a critical defense mechanism employed to mitigate oxidative damage and regulate apoptosis. These findings provide comprehensive insights into the metabolic remodeling and stress response strategies of mud crabs under low salinity stress.
盐度是调节水生甲壳类动物生理稳态的关键非生物因素。为阐明拟穴青蟹（Scylla paramamosain，埃斯唐帕多，1950）适应低盐度的生理和分子机制，将个体置于低盐度（3‰）和对照（28‰）条件下7天。生理分析表明，低盐度胁迫在肝胰腺中诱导了显著的氧化应激和组织损伤，其特征为超氧化物歧化酶（SOD）活性显著增加（增加了32.27%）、过氧化氢酶（CAT）活性显著增加（增加了56.23%）、总抗氧化能力（T-AOC）显著增加（增加了152.68%）以及天冬氨酸转氨酶（AST）活性显著增加（增加了24.77%）。转录组分析鉴定出489个差异表达基因（DEG），包括268个上调基因和221个下调基因。功能富集分析表明，拟穴青蟹通过增强跨膜离子转运并同步激活“精氨酸和脯氨酸代谢”来调节细胞内有机渗透物，从而适应低渗环境。同时，p53信号通路的显著激活表明其采用了一种关键的防御机制来减轻氧化损伤并调节细胞凋亡。这些发现为拟穴青蟹在低盐度胁迫下的代谢重塑和应激反应策略提供了全面的见解。
