作　　者： ; ; ; ; (陈昆平）;

机构地区： 中国水产科学研究院珠江水产研究所

出　　处： 《淡水渔业》 2017年第1期3-11,共9页

摘　　要： 为了探究补体C9在尼罗罗非鱼(Oreochromis niloticus)免疫中发挥的作用,本研究克隆并分析了尼罗罗非鱼补体C9基因(OnC9)。结果显示:OnC9的cDNA序列全长2 502 bp,包含1 761 bp的开放阅读框(ORF),编码586个氨基酸。氨基酸序列同源性分析表明,OnC9与牙鲆(Paralichthys olivaceus)补体C9氨基酸相似性最高,达73.0%,与其他鱼类补体C9的相似性介于49.3%~71.4%之间。实时荧光定量PCR检测结果表明,OnC9基因在所检测的各个组织或器官中表达水平有明显差异,在肝脏中表达量最高,其次是肠道、后肾、皮肤、肌肉、鳃,在脑、脾脏、心脏、头肾、胸腺和血液中表达量最低。在无乳链球菌(Streptococcus agalactiae)感染鱼体后,肝脏、后肾等组织中OnC9表达量表现为在感染12 h、48 h(或36 h)、120 h先后出现三个峰值的波动表达的规律。说明OnC9在无乳链球菌感染尼罗罗非鱼后的免疫应答中发挥作用。 As a member of the complement system,complement 9（ C9） plays a key role in forming the pore- like membrane attack complex（ MAC） of complement on target cells,which has the function of pore forming and is the effective component leading to cell lysis. In the present study,a full- length C9（ OnC9） c DNA of Oreochromis niloticus was 2 502 bp,containing 1 761 bp open reading frame,encoding 586 amino acids. The deduced amino acid sequence of OnC9 shared73. 0% similarity with PoC9（ Paralichthys olivaceus C9）,and 49. 3%- 71. 4% identity with the C9 of other teleosts. Real- time quantitative PCR（ q PCR） analysis demonstrated that the expression level of OnC9 in different tissues of O. niloticus was significantly different,and the highest level was detected in the liver; the lower level was detected in intestine,kidney,gills,skin and muscle and the lowest level was detected in brain,spleen,heart,head kidney,thymus and blood. The expression of OnC9 in liver,kidney and the other tissues appeared three peaks fluctuating at 12 hours,48（ or 36） hours and120 hours after infection of Streptococcus agalactiae. The results suggested that OnC9 may play an important role in tilapia immune response of anti- bacteria.

关 键 词： 尼罗罗非鱼 补体 无乳链球菌 组织表达分析

领　　域： [农业科学]