背景:了解干扰素(IFN)信号传导被负调节的机制对于保持先天免疫反应的平衡至关重要,作为先天免疫系统的功能,比如原来的屏障,对抗对主机的威胁。尽管脑心肌炎病毒(EMCV)病毒蛋白在拮抗先天免疫中的功能与早期研究有关,病毒蛋白3(VP3)在I型IFN中的作用的确切机制尚未得到充分阐明。
方法:使用Western印迹评估VP3表达和属于I型IFN途径表达水平的许多其他衔接子分子。IFN和其他抗病毒基因,如干扰素刺激基因(ISGs)15和56,通过实时定量聚合酶链反应(RT-qPCR)进行评估。利用50%组织培养感染剂量(TCID50)测定来探索VP3对人胚肾(HEK293)细胞中EMCV增殖的影响。使用免疫共沉淀(Co-IP)测定和共聚焦显微镜分析来研究VP3介导的潜在机制。
结果:我们发现EMCV的VP3是先天免疫反应的抑制剂。VP3水平的增加通过调节先天免疫信号通路和抑制抗病毒反应来增强病毒繁殖。其他信息表明,在病毒感染期间,EMCV的VP3增强自噬,并与线粒体抗病毒信号蛋白(MAVS)特异性相互作用,导致其在依赖于p62的自噬途径中降解。
结论:我们的研究结果表明,EMCV开发了一种策略,通过使用自噬来分解控制宿主病毒感染后先天免疫反应的蛋白质来对抗宿主的抗病毒防御。值得注意的是,VP3在此过程中起着重要作用。总的来说,这些发现可能为EMCV提供新的治疗靶点.
BACKGROUND: Understanding the mechanisms through which interferon (IFN) signaling is negatively regulated is crucial for preserving the equilibrium of innate immune reactions, as the innate immune system functions, such as the original barrier, combat threats to the host. Although the function of the encephalomyocarditis virus (EMCV) viral proteins in antagonizing innate immunity has been related to earlier studies, the precise mechanism underlying the role of viral protein 3 (VP3) in type I IFN has yet to be fully illuminated.
METHODS: VP3 expression and many other adaptor molecules belonging to type I IFN pathway expression levels were evaluated using Western blotting. The IFN and other antiviral genes, such as interferon-stimulated genes (ISGs) 15 and 56, were assessed by real-time quantitative polymerase chain reaction (RT-qPCR). A 50% tissue culture infectious dose (TCID50) assay was utilized to explore the effect of VP3 on EMCV proliferation in human embryonic kidney (HEK293) cells. Co-immunoprecipitation (Co-IP) assays and confocal microscope analysis were used to investigate the underlying mechanisms mediated by VP3.
RESULTS: We discovered that the VP3 of EMCV acts as a suppressor of innate immune reactions. Increased levels of VP3 enhance viral reproduction through modulation of innate immune signaling pathways and suppression of antiviral responses. Additional information indicated that during viral infection, the VP3 of EMCV enhances autophagy and interacts specifically with mitochondrial antiviral signaling protein (MAVS), leading to its degradation in an autophagy pathway that relies on p62.
CONCLUSIONS: Our findings showed that EMCV developed a tactic to combat host antiviral defenses by using autophagy to break down a protein that controls the innate immune response following a viral infection of the host. Notably, VP3 plays an important role in this process. Overall, these discoveries may provide a novel therapeutic target for EMCV.