Ren Liping, Wang Rixin, Xu Tianjun
Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan 316022, China.
Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan 316022, China.
Fish Shellfish Immunol. 2014 Sep;40(1):61-8. doi: 10.1016/j.fsi.2014.06.022. Epub 2014 Jun 26.
Caspase proteins are intracellular proteases which function as initiators and effectors of apoptosis. According their difference of functions, the caspases can be divided into apoptosis related caspases and inflammatory mediator, and the former included apoptosis activator and apoptosis executioner. In this study, three different subtype caspases (caspase1, caspase3 and caspase9) from Miichthys miiuy miiuy croaker were analyzed. The caspase1 belongs to the inflammatory mediator, caspase3 belongs to apoptosis executioner, and caspase9 belongs to apoptosis activator. Miichthys miiuy caspase1 (Mmcaspase1) and Mmcaspase9 exhibited three conserved domains including a CARD, a large subunit p20 and a small subunit p10. The Mmcaspase3 encoded two conserved domains including a large subunit p20 and a small subunit p10. Mmcaspase3 and Mmcaspase9 contained a histidine active sequence and a cysteine active sequence. However, Mmcaspase1 only contained the cysteine active sequence. The real-time PCR (RT-PCR) analysis showed these three caspases were expressed constitutively in all examined tissues in miiuy croaker, although the expression levels varied from tissue to tissue. Expression analysis showed that Mmcaspase1 was up-regulated obviously in liver, spleen and kidney, and indicated its positive role in response to Vibrio anguillarum infection, but Mmcaspase3 and Mmcaspase9 showed different expression pattern in liver, spleen and kidney, its showed that different subtypes of caspase having different immune response mechanisms. These results revealed that the organs adjusted the expressions of these three genes with the infected of pathogens, suggesting the immunoprotection of these genes.
半胱天冬酶蛋白是细胞内蛋白酶，作为细胞凋亡的启动子和效应器发挥作用。根据其功能差异，半胱天冬酶可分为凋亡相关半胱天冬酶和炎症介质，前者包括凋亡激活剂和凋亡执行者。在本研究中，分析了来自鮸状黄姑鱼鮸状黄姑鱼的三种不同亚型的半胱天冬酶（半胱天冬酶1、半胱天冬酶3和半胱天冬酶9）。半胱天冬酶1属于炎症介质，半胱天冬酶3属于凋亡执行者，半胱天冬酶9属于凋亡激活剂。鮸状黄姑鱼半胱天冬酶1（Mmcaspase1）和Mmcaspase9表现出三个保守结构域，包括一个CARD、一个大亚基p20和一个小亚基p10。Mmcaspase3编码两个保守结构域，包括一个大亚基p20和一个小亚基p10。Mmcaspase3和Mmcaspase9包含一个组氨酸活性序列和一个半胱氨酸活性序列。然而，Mmcaspase1仅包含半胱氨酸活性序列。实时PCR（RT-PCR）分析表明，这三种半胱天冬酶在鮸状黄姑鱼所有检测组织中均有组成性表达，尽管表达水平因组织而异。表达分析表明，Mmcaspase1在肝脏、脾脏和肾脏中明显上调，表明其在应对鳗弧菌感染中发挥积极作用，但Mmcaspase3和Mmcaspase9在肝脏、脾脏和肾脏中表现出不同的表达模式，这表明不同亚型的半胱天冬酶具有不同的免疫反应机制。这些结果表明，器官随着病原体的感染而调节这三个基因的表达，提示这些基因具有免疫保护作用。
