摘要
【目的】明确草鱼Toll样受体(Toll-like receptor,TLR)信号通路基因在防御多子小瓜虫(Ichthyophthiriusmultifiliis)感染过程中的免疫作用,为有效防控鱼类多子小瓜虫感染提供理论参考。【方法】以多子小瓜虫感染草鱼后,采用实时荧光定量PCR检测分析在不同时间点(感染后6 h、12 h、1 d、2 d、3 d、5 d和7 d)草鱼部分TLRs基因(TLR1、TLR2、TLR4、TLR9、TLR20和TLR21)、接头蛋白基因(MyD88和TRIF)、信号转导分子(IRAK4和IRAK1)及细胞因子(IL-1β、TNF-α和IFN)在其皮肤和脾脏中的表达动态变化。【结果】草鱼感染多子小瓜虫后,TLR1、TLR2、TLR9、TLR20和TLR21基因在皮肤和脾脏中的表达主要呈上调趋势,TLR4基因在皮肤中主要呈上调表达,在脾脏中则主要呈下调表达;TLR信号通路接头蛋白基因MyD88和TRIF的表达变化趋势明显不同,其中,MyD88基因的表达在感染后第1~3 d均呈显著上调趋势(P<0.05,下同),而TRIF基因的表达在整个试验过程中绝大多数时间点与对照组无显著差异(P>0.05);IRAK4和IRAK1在皮肤和脾脏中的表达也主要呈上调趋势,但在脾脏中IRAK4在感染后第1 d和IRAK1在感染后第6 h的表达呈显著下调趋势;IL-1β和TNF-α在绝大多数时间点均显著上调,但IFN的表达基本没有变化。【结论】草鱼TLR信号通路中的部分TLRs基因(TL1、TLR2、TLR4、TLR9、TLR20和TLR21)、接头蛋白基因(MyD88)、信号转导分子(IRAK4和IRAK1)及下游细胞因子(IL-1β和TNF-α)均参与防御多子小瓜虫感染的免疫反应,尤其是在感染早期和中期发挥关键作用。
【Objective】The immune defense function of some genes in toll-like receptor(TLR)signaling pathway of grass carp(Ctenopharyngodon idella)against Ichthyophthirius multifiliis infection was clarified to provide theoretical reference for the effective prevention and control of Ⅰ. multifiliis infection on fish.【Method】After I. multifiliis infection on C. idella,the real-time fluorescent quantitative PCR was employed to examine and analyze the dynamics of gene expression profiles in the skin and spleen of the C. idella at different time points,including 6 h,12 h,1 d,2 d,3 d,5 d,and 7 d.These tested genes contained several TLRs genes(TLR1,TLR2,TLR4,TLR9,TLR20,and TLR21),adaptor proteins genes(MyD88 and TRIF),signal transducing molecules(IRAK4 and IRAK1),and cytokines(IL-1β,TNF-α,and IFN).【Result】Several TLRs,including TLR1,TLR2,TLR9,TLR20,and TLR21,were up-regulated in the skin and spleen at most time points after I. multifiliis infection. The expression of TLR4 was mostly up-regulated in the skin,but down-regulated in the spleen. The expression trends of two adaptor proteins genes(MyD88 and TRIF)were obviously different.MyD88 expression showed significant up-regulation from day 1 to day 3 after I. multifiliis infection(P<0.05,the same below),whereas the expression levels of TRIF showed no significant changes at most time points compared with control(P>0.05). The expressions of both IRAK4 and IRAK1 also were up-regulated in the skin and spleenat most time points. However,the expressions of IRAK4 at day 1 and IRAK1 at 6 h in the spleen were significantly down-regulated after infection,respectively. The expressions of IL-1β and TNF-α were significantly up-regulated at most time points after infection,but the expression of IFN remained substantially unchanged.【Conclusion】The several genes in TLR signaling pathway of C.idella,including some TLRs genes(TLR1,TLR2,TLR4,TLR9,TLR20,and TLR21),one adaptor protein gene(MyD88),two signal transducing molecules(IRAK4 and IRAK1),and two downstream cytokines(IL-1β and TNF-α),are widely involved and play crucial roles in the immune defense against Ⅰ. multifiliis infection,especially in the early and middle stages of the infection.
作者
赵飞
谭爱萍
孔璐璐
刘付翠
邓玉婷
潘厚军
张瑞泉
姜兰
ZHAO Fei;TAN Ai-ping;KONG Lu-lu;LIU Fu-cui;DENG Yu-ting;PAN Hou-jun;ZHANG Rui-quan;JIANG Lan(Pearl River Fisheries Research Institute,Chinese Academy of Fishery Sciences/Key Laboratory of Fishery Drug Development,Ministry of Agriculture and Rural Affairs/Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province,Guangzhou 510380,China;College of Fishery and Life Science,Shanghai Ocean University,Shanghai 201306,China)
出处
《南方农业学报》
CAS
CSCD
北大核心
2019年第9期1885-1892,共8页
Journal of Southern Agriculture
基金
国家自然科学基金项目（31402338）
广东省自然科学基金项目（2015A030310137）
广东省级鱼病防治专项（粤财农〔2014〕585号）
广州市科技计划项目（201803020045）
关键词
草鱼
多子小瓜虫
Toll样受体(TLR)
信号通路
基因表达
Ctenopharyngodon idella
Ichthyophthirius multifiliis
toll-like receptor(TLR)
signaling pathway
gene expression
