National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan 316022, PR China.
National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan 316022, PR China.
Fish Shellfish Immunol. 2017 Nov;70:361-371. doi: 10.1016/j.fsi.2017.08.018. Epub 2017 Aug 18.
Superoxide dismutases (SODs), a by-product of antioxidative defence system, protects organisms for eliminating excess reactive oxygen species (ROS) and maintaining the redox balance of immune system. The complete open reading frames (ORFs) of Cu/Zn-SOD and Mn-SOD were identified from Mytilus coruscus (designated as McSOD and MnSOD) by homologous cloning. The sequence lengths were 474bp and 687bp, encoding 157 and 228 amino acids respectively. The deduced amino acid sequences of McSOD and MnSOD shared high identities with Cu/Zn-SOD and Mn-SOD from other mollusca. The distributions of McSOD and MnSOD were detected in six tissues including adductor, hemocyte, gill, gonad, mantle and hepatopancreas, and the highest expressions were both in gills. The temporal expression of McSOD and MnSOD were up-regulated in gills under a variety of stress factors, including Vibrio parahemolyticus, Aeromonas hydrophila, Cu and Pb. After being challenged with V. Parahemolyticus, the expressions of McSOD and MnSOD were increased rapidly at the initial hours, reaching the peaks of 4.9-fold and 15.3-fold respectively, and got to the highest levels of 43.5-fold and 7.1-fold after being challenged with A. hydrophila. The highest point of McSOD mRNA appeared at 15 d after being exposed to copper (7-fold at 0.5 mg/L and 13.2-fold at 1.5 mg/L), except for 0.1 mg/L group of Cu maintaining to the normal level, but plumbum at 1 d (2.4-fold at 1.0 mg/L and 4.4-fold at 3.0 mg/L) and at 15 d (2.1-fold at 0.2 mg/L). The temporal expression peaks of MnSOD appeared differently after exposing to copper of various concentrations (0.1 mg/L at 10 d with 4.7-fold, 0.5 mg/L at 1 d with 17.9-fold and 1.5 mg/L at 3 d with 13.2-fold). Whereas in plumbum exposing treatments, the 3.0 mg/L group jumped to the peak at 1 d (18.2-fold), the 0.2 mg/L and 1.0 mg/L groups had little change and maintained at the normal level throughout the experiment. The results provided several new evidences for further understanding of the regulatory mechanism of SOD on the innate immune system in bivalve.
超氧化物歧化酶（SODs）是抗氧化防御系统的一种副产物，它可以保护生物清除多余的活性氧（ROS）并维持免疫系统的氧化还原平衡。通过同源克隆，从贻贝（Mytilus coruscus）中鉴定出铜/锌-SOD 和 Mn-SOD 的完整开放阅读框（ORFs）（分别命名为 McSOD 和 MnSOD）。序列长度分别为 474bp 和 687bp，分别编码 157 和 228 个氨基酸。McSOD 和 MnSOD 的推导氨基酸序列与来自其他软体动物的 Cu/Zn-SOD 和 Mn-SOD 具有高度的同一性。McSOD 和 MnSOD 在包括贻贝、血细胞、鳃、性腺、套膜和肝胰腺在内的六种组织中均有分布，在鳃中表达最高。在受到各种应激因子（包括副溶血弧菌、嗜水气单胞菌、铜和铅）的刺激后，McSOD 和 MnSOD 在鳃中的表达均上调。在受到副溶血弧菌的刺激后，McSOD 和 MnSOD 的表达在最初的几个小时内迅速增加，分别达到 4.9 倍和 15.3 倍的峰值，在受到嗜水气单胞菌的刺激后，表达量达到 43.5 倍和 7.1 倍的最高水平。在暴露于铜（0.5mg/L 时为 7 倍，1.5mg/L 时为 13.2 倍）和铅（1.0mg/L 时为 2.4 倍，3.0mg/L 时为 4.4 倍）15d 后，McSOD mRNA 的最高水平出现在 15d，除了 0.1mg/L 组的铜保持在正常水平外，但在 1d 时（1.0mg/L 时为 2.1 倍）和 15d 时（0.2mg/L 时为 4.4 倍）。MnSOD 在暴露于不同浓度铜（0.1mg/L 时为 10d，4.7 倍；0.5mg/L 时为 1d，17.9 倍；1.5mg/L 时为 3d，13.2 倍）后的表达峰值出现不同。而在铅暴露处理中，3.0mg/L 组在 1d 时跃升至峰值（18.2 倍），0.2mg/L 和 1.0mg/L 组变化不大，整个实验过程中均保持在正常水平。研究结果为进一步了解 SOD 对贝类先天免疫系统的调节机制提供了新的证据。
