Xu Youhou, Huang Yucong, Cai Shuanghu
Guangxi Key Laboratory of Beibu Gulf Marine Biodiversity Conservation, Qinzhou University, Qinzhou, China.
Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals & Key Laboratory of Control for Diseases of Aquatic Economic Animals of Guangdong Higher Education Institutes, Fisheries College of Guangdong Ocean University, Zhanjiang, China.
Fish Shellfish Immunol. 2017 Feb;61:111-119. doi: 10.1016/j.fsi.2016.12.030. Epub 2016 Dec 24.
The interleukin-1 receptor-associated kinase-1 (IRAK-1) is an important adapter protein which links downstream of MyD88, and involved in the complex composed of MyD88 and TRAF6 to activate TLRs signaling pathway. In this study, an IRAK-1 homolog (FpIRAK-1) was cloned from the red tail shrimp Fenneropenaeus penicillatus. The ORF of FpIRAK-1 consisted of 2874 bp encoding a protein of 957 amino acids which contains a death domain (DD) and a catalytic domain of serine/threonine kinases (STKc). Homology analysis revealed that the predicted amino acid sequence of FpIRAK-1 shared 71% similarities with IRAK-1 of Litopenaeus vannamei. Real-time RT-PCR indicated that FpIRAK-1 was constitutively expressed in various tissues of F. penicillatus. The expression level of FpIRAK-1 mRNA was significantly up-regulated and then decreased gradually after white spot syndrome virus (WSSV) and Vibrio alginolyticus challenge. Gene knockdown of FpIRAK-1 enhanced the sensitivity of shrimps to WSSV and V. alginolyticus challenge, suggesting FpIRAK-1 could play a positive role against bacterial and viral pathogens. In conclusion, the results of this study provide some insights into the function of FpIRAK-1 in activating Toll signaling pathway and the host defense against invading pathogens.
白细胞介素-1受体相关激酶-1（IRAK-1）是一种重要的衔接蛋白，连接MyD88下游，并参与由MyD88和TRAF6组成的复合物以激活TLRs信号通路。在本研究中，从红尾虾凡纳滨对虾中克隆到一个IRAK-1同源物（FpIRAK-1）。FpIRAK-1的开放阅读框由2874个碱基对组成，编码一个957个氨基酸的蛋白质，该蛋白质包含一个死亡结构域（DD）和一个丝氨酸/苏氨酸激酶催化结构域（STKc）。同源性分析显示，FpIRAK-1预测的氨基酸序列与南美白对虾的IRAK-1有71%的相似性。实时RT-PCR表明，FpIRAK-1在凡纳滨对虾的各种组织中组成性表达。在白斑综合征病毒（WSSV）和溶藻弧菌攻击后，FpIRAK-1 mRNA的表达水平显著上调，然后逐渐下降。FpIRAK-1基因敲低增强了对虾对WSSV和溶藻弧菌攻击的敏感性，表明FpIRAK-1可能在抵抗细菌和病毒病原体方面发挥积极作用。总之，本研究结果为FpIRAK-1在激活Toll信号通路和宿主抵御入侵病原体方面的功能提供了一些见解。
