长链非编码RNA AVIRL在抗流感病毒感染中的作用机制研究

Long noncoding RNAs (lncRNAs) are RNA transcripts that are longer than 200 nucleotides and have no functional protein-coding or polypeptide-coding activity. More and more studies have suggested that lncRNAs are involved in multiple physiological and pathological progresses. Although there have been increasing studies on lncRNAs and diseases, the relationship between lncRNAs and influenza virus infection still needs to be further determined. In previous study, we have constructed the co-expression network of lncRNAs-mRNA during influenza virus infection and found that knockdown of lncRNA-AVIRL could significantly increase the replication of influenza virus. Based on this finding, in this project we will clarify the functional region of lncRNA-AVIRL and construct the AVIRL-mRNA/lncRNA co-expression network. Furthermore, using bioinformatics analysis, RNA pull down and RIP experiments, we will reveal the molecular basis of function of lncRNA-AVIRL during influenza virus infection. In addition, we will use a combination of mAVIRL（homologous gene of AVIRL in mouse）-knockdown or knockout mice, RIG-I knockout and IFNAR knockout mice to study the mechanism underlying function of mAVIRL during influenza virus infection. Taken together, these experiments using in vivo and in vitro models will provide an important and a novel contribution to our understanding of role and its mechanism for lncRNA-AVIRL in pathogenesis of influenza virus, and may highlight lncRNA-AVIRL as a candidate therapeutic target for the treatment of influenza virus.

越来越多的研究表明，长链非编码RNA (lncRNAs)参与了机体的多种生理和病理过程，但其作用机制，特别是在宿主抗病毒感染中的作用机制仍然亟待深入研究。前期研究中我们构建了流感病毒感染靶细胞的lncRNA-mRNA共表达网络，通过病毒血凝和噬斑实验发现干扰lncRNA-AVIRL显著促进流感病毒复制，过表达则抑制流感病毒的复制。本项目在此基础上构建AVIRL-mRNA/lncRNA共表达网络，结合生物信息学分析以及RNA pull down、RIP等实验，研究AVIRL抗病毒作用的分子基础。同时构建干扰或敲除小鼠中AVIRL同源基因mAVIRL的工程小鼠，并利用本实验室已有的RIG-I和I类干扰素受体IFNAR基因敲除小鼠，对AVIRL在病毒感染中的作用机制进行深入研究。本项目将从分子、细胞、动物水平上阐明AVIRL在抗流感病毒感染中的作用机制，为揭示流感病毒的致病机理提供新的科学依据。

流感病毒是影响人类健康和经济发展的重要疾病，是全球公众健康的主要威胁之一。目前研究发现，越来越多的长链非编码RNA参与了机体的生理和病理过程。本项目我们筛选了一条功能性长链非编码RNA AVIRL（说明：为更好的描述该长链非编码RNA，将其命名为，RIG-I-dependent IAV-upregulated noncoding RNA 简称：RDUR，小鼠中相应的同源分子命名为mRDUR），其在流感病毒感染后发生了上调。体内外实验研究发现，RIG-I/MAVS/NF-κB调控长链非编码RNA RDUR的表达。实验显示，当过表达宿主细胞中的RDUR基因，会抑制宿主细胞中流感病毒的复制，敲低则促进了流感病毒的复制。我们进一步制备了长链非编码RNA RDUR敲除的小鼠模型，体内实验显示，与野生型对照相比，病毒感染敲除RDUR基因的小鼠时，小鼠的肺脏病变更加严重，而且死亡更快。另外，我们发现长链非编码RNA RDUR通过上调干扰素和干扰素刺激基因，来抑制病毒的复制。有趣的是，在流感病毒感染过程中，在NF-κB调控长链非编码RNA RDUR表达的同时，负反馈调节NF-κB的活化，从而抑制了炎症因子的过度表达。总之，长链非编码RNA RDUR在宿主抗病毒免疫反应中，是一个重要的调控因子。