斑点叉尾鮰TLR5和TLR5S基因在不同病原诱导下的表达特征  

Gene expression of TLR5 and TLR5S in channel catfish Ictalurus punctatus induced by different pathogens

作　　者：李敏[1,2] 李琪[1] 王启龙[2] 路飏[2] 陈松林[2] 沙珍霞[2] 

机构地区：[1]中国海洋大学水产学院,青岛266003 [2]农业部海洋渔业可持续发展重点实验室中国水产科学研究院黄海水产研究所,青岛266071

出　　处：《渔业科学进展》2012年第5期30-38,共9页Progress in Fishery Sciences

基　　金：国家自然科学基金项目(30871941);人事部留学归国人员项目共同资助

摘　　要：分别用迟钝爱德华氏菌Edwardsiella tarda、嗜水气单胞菌Aeromonas hydrophila、链球菌Streptococcus iniae和斑点叉尾鮰呼肠孤病毒(channel catfish hemorrhage reovirus,CCRV)对斑点叉尾鮰Ictalurus punctatus进行感染实验,取感染后0h、12h、24h、48h、72h和7d的头肾、肠、肝脏和脾脏,采用实时定量PCR方法检测了TLR5和TLR5S基因在这4种免疫相关组织中的时空表达特征,探讨它们与斑点叉尾鮰先天免疫反应的关系。结果表明,链球菌和迟钝爱德华氏菌能够引起TLR5和TLR5S强烈的上调表达,其中以感染链球菌12h后TLR5S在头肾中的表达上调量最为显著,与对照组相比提高了132倍(P<0.01)。在感染嗜水气单胞菌后的24h内TLR5和TLR5S基因的表达量上升,但随后却显示出了明显的下调趋势,而斑点叉尾鮰呼肠孤病毒在TLR5和TLR5S基因表达中起到了明显的抑制作用,于大部分组织中表达下调。在感染12h的脾脏中,TLR5基因的表达量仅为对照组的0.017倍(P<0.01),而TLR5S基因表达量达到最低,仅为对照组的0.01倍(P<0.01)。从不同的组织来看,TLR5在肠中的表达上调幅度最大,而TLR5S在头肾中的表达增幅最明显,如感染链球菌和迟钝爱德华氏菌12h后,TLR5在肠中的表达量分别增加了50.4倍(P<0.01)和14.8倍(P<0.01),TLR5S在头肾中的表达量分别上升了52.8倍(P<0.01)和132倍(P<0.01)。以上结果进一步证明了TLR5和TLR5S基因在斑点叉尾鮰先天免疫反应过程中发挥着非常重要的作用,同时在抗病原侵袭过程中表现出了一定的组织特异性和病原特异性。Expression of channel catfish TLR5 and TLRSS genes in the testine, liver and spleen were analyzed by quantitative real-time PCR method h, 48 h, 72 h and 7 d after infection with Edwardsiella tarda, Aeromonas hy head kidney, in at 0 h, 12 h, 24 drophila , Strep tococcus iniae and channel catfish hemorrhage reovirus （CCRV）, respectively. The results showed that TLR5 and TLRSS mRNAs were largely up-regulated by E. tarda and S. iniae and the most significant increase of TLR5S gene expression occurred in head kidney 12h after being challenged with S. iniae, which was 132-fold higher than the PBS control. After infection with A. hydrophila, TLR5 and TLR5S showed up-regulation at 12h and 24h and obvious down-reg- ulation at 48h to 7d post-infection. TLR5 and TLRSS genes expression were suppressed by in- fection with CCRV in most tissues. In spleen, the expression of TLR5 was 0. 017-fold while TLRSS was only 0.01-fold compared with PBS control. Among the four immune-related differ- ent tissues, the expression of TLR5 and TLRSS showed significant up-regulation in intestine and head kidney. For example, after being challenged with E. tarda and S. iniae, at time point of 12h, the expression of TLR5 increased 50.4-fold and 14.8-fold respectively in intestine, and the expression of TLRSS increased 52.8-fold and 132-fold respectively in head kidney. All data suggested that TLR5 and TLR5S were involved in the immune response of channel catfish a- gainst the intracellular bacterial and virus pathogen in a tissue-specific and pathogen-specific manner, and further confirmed that both of them played significant roles in the channel catfish innate immunity.

关 键 词：斑点叉尾鮰 先无免疫 TLR5 TLR5S 基因表达 病原 

分 类 号：S917.4[农业科学—水产科学]