State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, 410081, China.
State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, 410081, China.
Dev Comp Immunol. 2020 Aug;109:103726. doi: 10.1016/j.dci.2020.103726. Epub 2020 May 4.
Receptor-interacting serine/threonine protein kinase 1 (RIPK1) is an important regulator of necroptosis and involved in innate immune response in human and mammal; however, its function in teleost fish mains largely unknown. In this paper, the RIPK1 homologue of black carp (Mylopharyngodon piceus) has been cloned and characterized to explore its role in immunity. Black carp RIPK1 (bcRIPK1) possesses the similar structure to its mammalian counterpart, which has been identified as a cytosolic protein by immunofluorescence staining. Overexpressed bcRIPK1 in host cells led to the decreased transcription of interferon (IFN) and interferon stimulated genes, and exogenous bcRIPK1 in EPC cells led to the decreased transcription of interferon promoters in reporter assay. Our previous study has identified that black carp MAVS (bcMAVS) functions as an antiviral adaptor protein against both grass carp reovirus (GCRV) and spring viremia of carp virus (SVCV). The reporter assay showed that the IFN-inducing ability of bcMAVS was dampened by bcRIPK1 and the plaque assay demonstrated that the antiviral activity of bcMAVS was inhibited by bcRIPK1. The immunofluorescent staining and co-immunoprecipitation identified the interaction between these two molecules. Thus, the data generated in this paper support the conclusion that bcRIPK1 interacts with bcMAVS and negatively regulates bcMAVS-mediated antiviral signaling.
受体相互作用丝氨酸/苏氨酸蛋白激酶 1（RIPK1）是调节细胞坏死和先天免疫反应的关键因子，在人类和哺乳动物中发挥重要作用；然而，其在硬骨鱼类中的功能仍知之甚少。本研究克隆并鉴定了草鱼（Mylopharyngodon piceus）RIPK1 同源物，以探索其在免疫中的作用。草鱼 RIPK1（bcRIPK1）具有与其哺乳动物对应物相似的结构，通过免疫荧光染色鉴定为胞质蛋白。过表达宿主细胞中的 bcRIPK1 导致干扰素（IFN）和干扰素刺激基因的转录减少，而外源性 bcRIPK1 在 EPC 细胞中导致报告基因检测中干扰素启动子的转录减少。我们之前的研究已经鉴定出草鱼 MAVS（bcMAVS）作为一种抗病毒衔接蛋白，可对抗草鱼呼肠孤病毒（GCRV）和鲤鱼出血病病毒（SVCV）。报告基因检测显示，bcRIPK1 减弱了 bcMAVS 的 IFN 诱导能力，蚀斑试验表明 bcRIPK1 抑制了 bcMAVS 的抗病毒活性。免疫荧光染色和共免疫沉淀鉴定了这两个分子之间的相互作用。因此，本文中的数据支持 bcRIPK1 与 bcMAVS 相互作用并负调控 bcMAVS 介导的抗病毒信号的结论。
