Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, Hunan 410128, China.
College of Animal Science/Key Laboratory of Animal Genetics and Breeding and Reproduction of Plateau and Mountain Animals of Guizhou University, Guiyang, Guizhou 550025, China.
Mol Immunol. 2022 Aug;148:81-90. doi: 10.1016/j.molimm.2022.05.120. Epub 2022 Jun 7.
Grass carp is an economically important freshwater fish in China, and haemorrhagic disease caused by GCRV has seriously restricted its farming scale. To understand the host molecular basis for antiviral defence and explore the effector molecules, a global transcriptional profiling of four major immune tissues (liver, spleen, head kidney, and trunk kidney) of GCRV-infected grass carp was established. A total of 192.65 Gb clean data was obtained with 6.11 Gb per sample and stored in the NCBI Sequence Read Archive (with accession number PRJNA759556). Based on the GO and KEEG analyses, 108 unique GO terms were enriched in the four tissues. Thirty-five enriched pathways were obtained, with 21 metabolism-related pathways mainly gained in the liver and trunk kidney, and 14 immune response pathways were enriched in the spleen and head kidney. Also demonstrated was that GCRV stimulates not only the expression of interferon-stimulated genes (ISGs) but also proinflammatory cytokines. 27 ISGs were screened from the candidate DEGs, and eight ISGs were identified for the first time in grass crap. These ISGs were classified into three categories by their function found in mammals: (i) positively regulates the IFN signalling pathway (RIG-I, MDA5, IRF7, IRF9, STAT2, and TRIM25); (ii) negatively regulates the IFN signalling pathway (usp18 and SOCS1); and (iii) exerts direct antiviral activity such as Mx1, ISG15, ISG56, ISG58, viperin, and PKR. Eight major ISGs and four typical differentially inflammatory cytokines were used for further expression analysis with prominent expression in the liver, spleen and kidney. The onset time of IFN-mediated antiviral response was trunk kidney (12-24 h) > liver (48 h) > spleen (96-120 h), and the intensity was liver > spleen > trunk kidney. Notably, the inflammatory reaction occurs early in the liver and trunk kidney. This result implies that ISGs may act synergistically and that the IFN response is closely related to the inflammatory response against GCRV infection. The transcriptomic profiles obtained and the function of ISGs predicted in this study provide new insights into fish antiviral mechanisms and developing effective therapeutic directions.
草鱼是中国重要的淡水养殖鱼类，而 GCRV 引起的草鱼出血病严重限制了其养殖规模。为了了解宿主抗病毒防御的分子基础并探索效应分子，我们对 GCRV 感染草鱼的四个主要免疫组织（肝、脾、头肾和体肾）进行了全转录组分析。共获得了 192.65 Gb 的清洁数据，每个样本的存储量为 6.11 Gb，并存储在 NCBI Sequence Read Archive 中（ accession number PRJNA759556）。基于 GO 和 KEEG 分析，在这四个组织中富集了 108 个独特的 GO 术语。获得了 35 个富集途径，其中 21 个与代谢相关的途径主要在肝和体肾中获得，14 个免疫反应途径在脾和头肾中富集。结果还表明，GCRV 不仅刺激干扰素刺激基因（ISGs）的表达，还刺激促炎细胞因子的表达。从候选 DEGs 中筛选出 27 个 ISGs，其中 8 个 ISGs首次在草鱼中被鉴定。这些 ISGs 根据其在哺乳动物中的功能分为三类：（i）正向调节 IFN 信号通路（RIG-I、MDA5、IRF7、IRF9、STAT2 和 TRIM25）；（ii）负向调节 IFN 信号通路（usp18 和 SOCS1）；和（iii）直接发挥抗病毒活性，如 Mx1、ISG15、ISG56、ISG58、viperin 和 PKR。进一步的表达分析采用 8 个主要的 ISGs 和 4 个典型的差异炎性细胞因子，在肝、脾和肾中均有明显表达。IFN 介导的抗病毒反应的起始时间为肾（12-24 h）> 肝（48 h）> 脾（96-120 h），强度为肝> 脾> 肾。值得注意的是，炎症反应在肝和肾中发生较早。这一结果表明，ISGs 可能协同作用，IFN 反应与草鱼 GCRV 感染的炎症反应密切相关。本研究获得的转录组谱和预测的 ISGs 功能为鱼类抗病毒机制的研究提供了新的视角，并为开发有效的治疗方向提供了依据。
