南方农业学报2024，Vol.55Issue(6)：1817-1827,11.DOI:10.3969/j.issn.2095-1191.2024.06.026
吉富罗非鱼IRF9基因克隆及表达特征分析
Cloning and expression characteristics analysis of IRF9 gene in GIFT Oreochromis niloticus
摘要
Abstract
[Objective]To clarify the structural characteristics and tissue expression patterns of the interferon regula-tory factor 9 gene(OnIRF9)in GIFT Oreochromis niloticus,and its immune response after infection with Streptococcus agalactis and stimulation with Poly(I∶C),which provided theoretical basis for revealing the function mechanism of IRF9 in immune response reaction of GIFT O.niloticus and enriching the immunological knowledge of IRF in fish.[Method]The cDNA sequence of the OnIRF9 gene was amplified by using RACE technology,bio-informatics analysis was per-formed by applying online softwares,such as ExPASy,SMART,TMHMM-2.0 and Euk-mPLoc 2.0,while real-time fluorescence quantitative PCR was used to detect the expression characterisitics of the OnIRF9 gene in healthy GIFT O.ni-loticus tissues and its expression changes after infection with S.agalactiae and stimulation with Poly(I∶C).[Result]The full-length cDNA sequence of OnIRF9 gene was 1828 bp,containing a 50 bp 5'-end non-coding region(5'-UTR),a 485 bp 3'-end non-coding region(UTR),and a 1293 bp open reading frame(ORF),encoding 430 amino acid residues.OnIRF9 protein had a molecular weight of 48.42 kD and a theoretical isoelectric point(pI)of 6.23 and contained two typi-cal IRF domains of DBD and I AD,without signal peptides and transmembrane domains.The amino acid sequence of OnIRF9 shared 56.2％-95.7％similarity with IRF9 amino acid sequences from other teleosts fish species,had the highest similarity with IRF9 amino acid sequences of Astatotilapia calliptera(95.7％).The phylogenetic tree constructed based on IRF9 amino acid sequence similarity showed that GIFT O.niloticus clustered with other reference fish species,particu-larly exhibiting the closest relationship with A.calliptera.The OnIRF9 gene was expressed in brain,blood,muscle,liver,skin,heart,spleen,head kidney,intestine and gill of healthy GIFT O.niloticus,with the highest relative expres-sion level in the brain,which was significantly higher than other tissues(P＜0.05),while the relative expression level in the gill was the lowest.After S.agalactiae infection and Poly(I∶C)stimulation,the expression levels of OnIRF9 gene were extremely significantly up-regulated within 6 h in the spleen,head kidney and brain(P＜0.01).However,the time at which the relative expression level reached its peak was not consistent,suggesting that the OnIRF9 gene might have complementary coordination in response to immune responses in various tissues.[Conclusion]OnIRF9 contains two typi-cal domains of IRF(DBD and IAD).Especially,the function of the DBD domain is relatively conserved in vertebrates.The OnIRF9 gene plays an important role in the central nervous system and is involved in the immune response reaction of GIFT O.niloticus in resisting pathogen invasion.关键词
吉富罗非鱼/干扰素调节因子9(IRF9)/无乳链球菌/Poly(I∶C)/免疫应答Key words
GIFT Oreochromis niloticus/interferon regulatory factor(IRF9)/Streptococcus agalactiae/Poly(I∶C)/immune response分类
农业科技引用本文复制引用
韩鹏夫,彭文,童桂香,纪月鑫,陈铭曲,文水平,韦信贤,韦友传..吉富罗非鱼IRF9基因克隆及表达特征分析[J].南方农业学报,2024,55(6):1817-1827,11.基金项目
National Natural Science Foundation of China(32160873) （32160873）
Guangxi Natural Science Foundation(2023GXNSFAA026502) （2023GXNSFAA026502）
Guangxi Special Freshwater Fish Innovation Team Disease Prevention and Control Post Func-tional Expert Project of China Agriculture Research System(nycytxgxcxtd-2021-08-02) 国家自然科学基金项目(32160873) （nycytxgxcxtd-2021-08-02）
广西自然科学基金项目(2023GXNSFAA026502) （2023GXNSFAA026502）
国家现代农业产业技术体系广西特色淡水鱼创新团队病害防控岗位功能专家项目(nycytxgxcxtd-2021-08-02) （nycytxgxcxtd-2021-08-02）
