Department of Marine Life Science, College of Ocean Science, Jeju National University, Jeju Special Self-Governing Province 690-756, Republic of Korea.
Comp Biochem Physiol B Biochem Mol Biol. 2009 Dec;154(4):387-95. doi: 10.1016/j.cbpb.2009.08.002. Epub 2009 Aug 20.
This study describes the transcriptional analysis of antioxidant and immune defense genes in gills tissue of disk abalone exposed to thermal, salinity and hypoxia-related stress, using quantitative real-time PCR. Results showed that manganese superoxide dismutase (MnSOD), copper zinc superoxide dismutase (CuZnSOD), catalase (CAT), thioredoxin peroxidase (TPx), selenium dependant glutathione peroxidase (SeGPx), and thioredoxin-2 (TRx-2) transcripts were expressed differently in gills, and that they respond collectively as a classical enzymatic antioxidant defense system in abalone. Comparative analysis of expression profiles indicated that CAT, TPx and SeGPx transcripts were significantly up-regulated (p<0.05) by all three physical stress conditions - thermal (28 degrees C), salinity (25 per thousand) and hypoxia - relative to levels in respective controls. In contrast, CuZnSOD and TRx-2 transcription were down-regulated in response to thermal stress. Interestingly, all the antioxidant transcripts exhibited significant up-regulation in response to salinity-related stress. Meanwhile, hypoxia caused up-regulation of the MnSOD, CAT, TPx and SeGPx, but not the CuZnSOD and TRx-2 transcripts. One of the most significant outcomes was the more than 10-fold induction of SeGPx, suggesting that SeGPx is a potential biomarker gene among antioxidant enzymes, under conditions of physical stress. The effects of physical stress on the transcriptional responses of immune functional genes namely suppressor of cytokine signaling-2 (SOCS-2) and myxovirus resistance (Mx) were investigated. We observed that salinity and hypoxia increase both the SOCS-2 and Mx transcripts, while thermal stress at 28 degrees C exerts less of an effect, producing mixed transcriptional responses (both up and down regulation). Based upon these results, we postulate that abalones utilize antioxidant and immune defense mechanisms together to overcome physical stresses.
本研究采用定量实时 PCR 技术，描述了热、盐度和缺氧相关应激下鲍鱼鳃组织中抗氧化和免疫防御基因的转录分析。结果表明，锰超氧化物歧化酶（MnSOD）、铜锌超氧化物歧化酶（CuZnSOD）、过氧化氢酶（CAT）、硫氧还蛋白过氧化物酶（TPx）、硒依赖谷胱甘肽过氧化物酶（SeGPx）和硫氧还蛋白-2（TRx-2）转录本在鳃中表达不同，它们作为一个经典的酶抗氧化防御系统在鲍鱼中共同起作用。表达谱的比较分析表明，CAT、TPx 和 SeGPx 转录本在所有三种物理应激条件下（28°C 的热、25‰的盐度和缺氧）均显著上调（p<0.05），与各自对照相比。相比之下，CuZnSOD 和 TRx-2 转录受到热应激的下调。有趣的是，所有抗氧化转录本在盐度相关应激下均显著上调。同时，缺氧导致 MnSOD、CAT、TPx 和 SeGPx 的上调，但 CuZnSOD 和 TRx-2 的转录本没有上调。最显著的结果之一是 SeGPx 的诱导超过 10 倍，表明 SeGPx 是抗氧化酶在物理应激条件下的潜在生物标志物基因。研究了物理应激对免疫功能基因即细胞因子信号转导抑制因子-2（SOCS-2）和粘液病毒抗性（Mx）转录响应的影响。我们观察到盐度和缺氧均增加了 SOCS-2 和 Mx 转录本，而 28°C 的热应激则产生了较少的影响，产生了混合的转录响应（上调和下调）。基于这些结果，我们假设鲍鱼利用抗氧化和免疫防御机制共同克服物理应激。
