Profiling anti-influenza activities of the pathogen recognition receptor RIG-I: Novel targets for antiviral intervention strategies

rig - 1是一种结合甲型流感病毒（FLUAV） 5 ' pp- dsrna长柄的细胞病毒传感器。rig - 1随后改变构象，可以通过夹紧长柄并分解聚合酶复合体来发挥直接的抗病毒作用，但通常它也会触发抗病毒信号，导致I型干扰素（IFN）的产生。我们已经产生了rig - 1突变体，尽管缺乏抗病毒信号，但它可以减少病毒RNA的合成。这些rig - 1突变体的抗病毒机制将通过定义最小所需结构域和进一步修饰来探索和优化。我们已经培育出携带这样一种rig - 1突变体（K271A）的小鼠，并将其与wt和rig - 1 KO小鼠的FLUAV抗性进行比较。帕特尔和库科尔（病毒学2017）预测，帕利哌酮是一种经fda批准的抗精神病药，可以结合PB2。研究显示，帕利哌酮可以模拟rig - 1的直接抗病毒活性，因为它可以减少PB2与核衣素的结合，并减少PR8/34菌株的RNA合成。我们将在细胞系和原代人气道细胞中测试帕利哌酮对多种流感病毒株的作用，研究rig - 1在其抗病毒作用中的潜在作用，并评估其与rig - 1激动剂的相互作用。此外，我们还鉴定了rrna衍生的自rna片段作为新的RIG-I配体。这些RIG-I刺激物可以由OAS/ RNase L产生，而OAS/ RNase L又可以被dsRNA和糖酵解中间体果糖-1,6-二磷酸（F16bP）激活。内源性糖酵解中间体与先天免疫之间的这种可能联系将在OAS/RNase L敲除细胞中进行后续研究。此外，将研究巨噬细胞代谢状态对RNase L激活、自身rna片段生成以及随后rig - i介导的抗病毒活性的影响。

RIG-I is a cellular virus sensor that binds the 5’ppp-dsRNA panhandle of Influenza A virus (FLUAV). RIG-I then switches conformation and can exert a direct antiviral effect by clamping onto the panhandle and disassembling the polymerase complex, but normally it also triggers antiviral signaling leading to type I interferon (IFN) production. We had generated mutants of RIG-I that reduce viral RNA synthesis despite being deficient in antiviral signaling. The antiviral mechanism of these RIG-I mutants will be explored and optimized by defining the minimally required domain and by further modifications. We already have created mice bearing one such RIG-I mutant (K271A), and will compare their FLUAV resistance with wt and RIG-I KO mice. Paliperidone, an FDA-approved antipsychotic predicted by Patel & Kukol (Virology 2017) to bind PB2, was shown to mimic the direct antiviral activity of RIG-I as it diminished the binding of PB2 to nucleocapsids and reduced RNA synthesis of the PR8/34 strain. We will test Paliperidone against a variety of FLUAV strains in cell lines and primary human airway cells, investigate a potential involvement of RIG-I in its antiviral effect, and evaluate its interplay with RIG-I agonists. Also, we identified rRNA-derived self-RNA fragments as new RIG-I ligands. These RIG-I stimulators can be generated by the OAS/ RNase L that in turn can be activated by dsRNA and the glycolysis intermediate Fructose-1,6-bisphosphate (F16bP). This possible link between an endogenous intermediate of glycolysis and innate immunity will be followed up in OAS/RNase L knockout cells. Moreover, the influence of the metabolic state of macrophages on RNase L activation, self-RNA fragment generation and subsequent RIG-I-mediated antiviral activity will be investigated.