尼罗罗非鱼γ-干扰素基因的克隆、结构分析及组织表达  

Cloning,structure analysis and expression of interferon gamma (IFN-γ) gene in Oreochromis niloticus

作　　者：余嘉欣 吴芳[1,2] 孙成飞[1] 董浚键[1] 田园园[1,2] 叶星[1,2] 

机构地区：[1]中国水产科学研究院珠江水产研究所,农业部热带亚热带水产资源利用与养殖重点实验室,广东广州510380 [2]上海海洋大学水产与生命学院,上海201306

出　　处：《南方水产科学》2017年第1期85-93,共9页South China Fisheries Science

基　　金：国家自然科学基金项目(31272688);国家高技术研究发展计划(863计划)项目(2011AA100404);现代农业产业技术体系建设专项资金(CARS-49)

摘　　要：γ-干扰素(interferon,IFN)是调控天然免疫与细胞免疫的一种重要细胞因子,在抵抗病毒入侵和细菌感染中发挥重要作用。该研究从尼罗罗非鱼(Oreochromis niloticus)脾脏组织中扩增到γ-干扰素基因的c DNA,大小为621 bp,编码206个氨基酸。生物信息学分析表明,尼罗罗非鱼γ-干扰素分子(On IFNγ)具有信号肽、IFN特征序列及核定位信号。预测的三级结构与人类IFNγ晶体结构最相似。q PCR检测显示,IFNγ在正常鱼体内的脾脏中表达量最高,其次是肠、鳃和肾脏。感染无乳链球菌(Streptococcus agalactiae)后,On IFNγ在脾脏、肾和鳃中的表达均显著上调(P<0.05)。On IFNγ在相关免疫器官中的高表达、受感染后的表达上调,说明其在罗非鱼免疫防御中可能具有重要作用。该研究为进一步开展On IFNγ基因的功能研究、探讨其在抗病转基因及抗病选育中的开发应用奠定了基础。Interferon-γ is a cytokine crucial for the regulation of both natural and cellular immunity,playing an important role in defending against virus invasion and bacterial infection. In this study,the c DNA of interferon-γ genes was amplified from the spleen tissues of Nile tilapia; this c DNA had an open reading frame of 621 bp,encodeing 206 amino acids. Bioinformatics analysis shows that the interferon-γ molecule of Nile tilapia contains one signal peptide and one nuclear localization signal. Its tertiary structure was similar with the crystal structure of human interferon-γ. Real-time fluorescent quantitative polymerase chain reaction（ PCR） shows that the expression level of interferon-γ gene was the highest in the spleen of normal Nile tilapia,followed by the intestines,gills and kidneys（ P 〈0. 05）. Both the high expression of interferon-γ in immune-associated tissues and its upregulated expression after GBS infection reveal the significant role of interferon-γ in the immune defense of Nile tilapia. This study lays foundation for further research on the function of interferon-γ gene in Nile tilapia as well as its development and application in transgenesis and selective breeding for disease resistance.

关 键 词：尼罗罗非鱼 Γ-干扰素 序列分析 结构分析 生物信息学 组织分布 

分 类 号：S917.4[农业科学—水产科学]