Stimulator of interferon genes (STING) has been demonstrated as a critical mediator in the innate immune response to cytosolic DNA and RNA derived from different pathogens. While the role of Micropterus salmoides STING (MsSTING) in largemouth bass virus is still unknown. In this study, RT-qPCR assay and Western-blot assay showed that the expression levels of MsSTING and its downstream genes were up-regulated after LMBV infection. Pull down experiment proved that a small peptide called Fusion peptide (FP) that previously reported to target to marine and human STING as a selective inhibitor also interacted with MsSTING in vitro. Comparing with the RNA-seq of Largemouth bass infected with LMBV singly, 326 genes were significantly up-regulated and 379 genes were significantly down-regulated in the FP plus LMBV group in which Largemouth bass was treatment with FP before LMBV-challenged. KEGG analysis indicated that the differentially expressed genes (DEGs) were mainly related to signaling transduction, infectious disease viral, immune system and endocrine system. Besides, the survival rate of LMBV-infected largemouth bass was highly decreased following FP treatment. Taken together, our study showed that MsSTING played an important role in immune response against LMBV infection.

干扰素基因刺激剂( STING ) 已被证明是对源自不同病原体的胞质 DNA 和 RNA 的先天免疫反应的关键介质。而鲑鱼STING ( MsSTING )在大口黑鲈病毒中的作用仍不清楚。本研究中，RT-qPCR检测和Western-blot检测显示LMBV感染后MsSTING及其下游基因的表达水平上调。 Pull down 实验证明，一种名为融合肽 (FP) 的小肽（之前报道作为选择性抑制剂靶向海洋和人类 STING）在体外也能与 MsSTING 相互作用。与单独感染LMBV的大口黑鲈的RNA-seq相比，在FP加LMBV组中，其中大口黑鲈在攻击LMBV之前用FP处理，有326个基因显着上调，379个基因显着下调。 KEGG分析表明差异表达基因(DEGs)主要与信号转导、传染病病毒、免疫系统和内分泌系统相关。此外，经FP处理后，感染LMBV的大口黑鲈的存活率大大降低。综上所述，我们的研究表明，MsSTING在针对 LMBV 感染的免疫反应中发挥着重要作用。