日本鳗鲡IFN-γ基因的鉴定、表达模式及启动子活性分析  

CHARACTERIZATION, EXPRESSION PATTERN AND PROMOTER ACTIVITY ANALYSIS OF INTERFERON-GAMMA IN JAPANESE EEL,ANGUILLA JAPONICA

作　　者：彭喜霞 黄贝[1] 段利朋 李春艳[1] 梁英[1] 聂品[1,2] 黄文树[1,3,4] 

机构地区：[1]集美大学水产学院,厦门361021 [2]中国科学院水生生物研究所淡水生态与生物技术国家重点实验室,武汉430072 [3]鳗鲡现代产业技术教育部工程研究中心,厦门361021 [4]福建省海洋生物资源开发利用协同创新中心,厦门361005

出　　处：《水生生物学报》2017年第3期589-602,共14页Acta Hydrobiologica Sinica

基　　金：国家自然科学基金(31402329;31174238和U1205123);福建省自然科学基金(2014J05042;2012J06008和JK2014026);鳗鲡工程中心科研基金资助~~

摘　　要：为揭示鱼类IFN-γ的生物学功能,研究从日本鳗鲡(Anguilla japonica)中克隆获得了IFN-γ基因,命名为Aj IFN-γ。Aj IFN-γ具有脊椎动物IFN-γ的典型特征:包括4外显子/3内含子的基因结构、C端的IFN-γ特征性氨基酸基序和1个核定位信号,以及6个α-螺旋反向平行构成的二级结构。Aj IFN-γ在日本鳗鲡所有组织中均低水平转录表达,其中肝脏中表达量最高,其次是皮肤和头肾。Poly I:C刺激和迟缓爱德华氏菌感染均可显著诱导Aj IFN-γ在鳃、头肾、体肾和(或)脾脏中的转录表达,表明Aj IFN-γ能够参与日本鳗鲡抗菌和抗病毒的免疫过程。此外,研究还克隆了Aj IFN-γ基因的5′调控区序列共1536 bp,并构建了一系列Aj IFN-γ5′调控区删节突变体,分析其启动子活性,结果表明,上游–240/+136区域中含有起始Aj IFN-γ转录的关键启动子调控元件,–1062/–814区域存在转录的正调控元件,而–1252/–1062区域存在转录的负调控元件。上述结果进一步丰富了鱼类IFN-γ的基础知识。IFN-γ is a cytokine that is critical for innate and adaptive immunity against viral, some bacterial and proto-zoal infections. In this study, an interferon-γ gene, named AjIFN-γ, was cloned and characterized from Japanese eel, An-guilla japonica. The AjIFN-γ shared some common features with its vertebrate homologues including a 4-exon/3-introngene structure, a typical IFN-γ characteristic motif and a predicted nuclear localization site in the predicted protein. AjI-FN-γ mRNA could be detected in all the tested tissues from healthy Japanese eel with the highest in liver, followed byskin and head kidney by real-time RT-PCR. A significantly increased expression of AjIFN-γ could be found in gill,head kidney, trunk kidney and （or） spleen post intraperitoneal injection with Poly I：C or Edwardsiella tarda, which in-dicated a role in defense of Japanese eel against both viruses and bacteria. Furthermore, luciferase reporter assaydemonstrated that the sequence from –240 bp to ＋136 bp in the 5′ flanking region of AjIFN-γ gene was essential for ini-tiating the transcription of AjIFN-γ, and the sequence form –1062 bp to –814 bp may contain some positive transcrip-tional regulatory elements while the sequence from –1252 bp to –1062 bp may contain negative transcriptional regula-tory elements. This study provided the basis for further investigation of the expanding functions of IFN-γ molecules inimmunity and other physiological processes in teleost and other animals.

关 键 词：IFN-Γ 日本鳗鲡 转录表达 启动子 

分 类 号：Q344.1[生物学—遗传学]