病原体识别系统涉及受体和基因,这些受体和基因在激活棕色大理石石斑鱼(Epinephelusfuscoguttatus)的先天免疫反应中起关键作用,作为针对包括弧菌病在内的各种感染的对照剂。这里,我们报道了部分开放阅读框的分子克隆,序列表征,和模式识别受体(PRR)在棕色大理石纹石斑鱼中的表达谱。PRR,即pglyrp5,tlr5,ctlD,和棕色大理石纹石斑鱼的ctlE,拥有保守的域,并显示出与其他鱼类的共同进化关系,人类,哺乳动物,鸟,爬行动物,两栖动物,和昆虫。在感染实验中,感染溶藻弧菌的棕色大理石纹石斑鱼鱼种的死亡率高达50%,而感染副溶血弧菌的死亡率为27%,对照组的存活率为100%。还证明了与副溶血性弧菌相比,所有四种PRR在感染溶藻弧菌的样品中具有更高的表达。该PRRs基因表达分析揭示,所有四个PRRs在接种后4小时快速表达,尽管在样品中仅在接种后12小时最早检测到弧菌计数。记录到的最高表达来自于溶藻弧菌接种的鱼脾脏,其中pglyrp5基因的变化高达73倍,随后在脾脏中进行相同处理的14至38倍表达,头肾,和其他PRR的血液样本,即tlr5,ctld,和ctlE基因。同时,在脾脏中检测到所有四个基因的表达增加不到10%,头肾,和接种副溶血性弧菌的血样。这些结果表明,pglyrp5,tlr5,ctlD,ctlE在弧菌病感染的早期免疫应答中起重要作用,棕色大理石纹石斑鱼鱼种。
The pathogen recognition system involves receptors and genes that play a crucial role in activating innate immune response in brown-marbled grouper (Epinephelus fuscoguttatus) as a control agent against various infections including
vibriosis. Here, we report the molecular cloning of partial open reading frames, sequences characterization, and expression profiles of Pattern Recognition Receptors (PRRs) in brown-marbled grouper. The PRRs, namely pglyrp5, tlr5, ctlD, and ctlE in brown-marbled grouper, possess conserved domains and showed shared evolutionary relationships with other fishes, humans, mammals, birds, reptilians, amphibians, and insects. In infection experiments, up to 50% mortality was found in brown-marbled grouper fingerlings infected with Vibrio alginolyticus compared to 27% mortality infected Vibrio parahaemolyticus and 100% survival of control groups. It is also demonstrated that all four PRRs had higher expression in samples infected with V. alginolyticus compared to V. parahaemolyticus. This PRRs gene expression analysis revealed that all four PRRs expressed rapidly at 4-h post-inoculation even though the Vibrio count was only detected earliest at 12-h post-inoculation in samples. The highest expression recorded was from V. alginolyticus inoculated fish spleen with up to 73-fold change for pglyrp5 gene, followed by 14 to 38-fold expression for the same treatment in spleen, head kidney, and blood samples for other PRRs, namely tlr5, ctlD, and ctlE genes. Meanwhile less than a 10% increase in expression of all four genes was detected in spleen, head kidney, and blood samples inoculated with V. parahaemolyticus. These findings indicated that pglyrp5, tlr5, ctlD, and ctlE play important roles in the early immune response to
vibriosis infected, brown-marbled grouper fingerlings.