NDV-vsRNA靶向NFkB信号通路调控新城疫病毒复制的作用机制

Viral small RNA (vsRNA) is a small non-coding RNA molecule (containing about 19-24 nucleotides) coding by virus gemone and functions in several biological pathways. Lost of studies showed that vsRNAs have been shown to play significant roles on virus infection and host immune responses. Deep sequencing was conducted on total RNA extracted from DF-1 and CEF cells that were infected with and without NDV NA-1 strain collected at 12, 24, 48 and 72 hours post infection (hpi), and results showed that one microRNA-like viral small RNA (NDV-vsRNA) was found to be derived from the 3’ UTR of the virus. Furthermore, RNA inhibitor of NDV-vsRNA was significantly silenced different genotype NDV replication in vitro. Therefore in this project we examine the regulate mechanism of a functional viral small RNA encoded by the 3’ untranslated region of Newcastle disease virus during its replication. Origin, regulated factors, target genes, regulation mechanism on NDV infection and host immune responses as well as clinical trial of NDV-vsRNA are conducted to explored the roles of NDV-vsRNA during NDV infection and host immune responses. The results obtained from this project not only extend the concept of linking NDV-host interactions during NDV infections, but also reveal potential novelty views and strategies of combat actions against Newcastle disease.

多种病毒通过编码产生的病毒小RNA（vsRNA）靶向改变病毒自身复制和感染或帮助病毒对抗和逃避宿主免疫监视等方式协助自身完成生命周期，然而vsRNA在新城疫病毒（NDV）复制中的功能和机制并未清晰。申请人前期发现NDV编码产生多种vsRNA, 其中3’端保守非编码区编码产生的vsRNA（NDV-vsRNA）能促进不同基因型NDV复制，并正向关联NDV复制必须的NFkB信号通路。本项目以NDV如何利用NDV-vsRNA来协助其复制为科学问题，以NDV-vsRNA与NFkB信号通路的相关性和调控NDV复制为切入点，采用细胞生物学、免疫学和分子生物学等技术，探索NDV-vsRNA的生物学特性，追踪NDV-vsRNA/NFkB信号通路轴在NDV感染周期中的信号传导作用或影响宿主天然免疫应答的机制，构建靶调NDV-vsRNA调节NDV感染的模型。最终从NDV-vsRNA角度剖析NDV与宿主互作机制。

miRNA已被证明能够参与病毒感染等多种生物学过程，调控转录后基因表达，而mRNA作为miRNA的下游分子，可充当效应分子直接参与病毒感染或宿主抗病毒免疫等多个环节。本项目利用高通量测序技术获得了NDV感染鸡胚内脏组织24 h和36 h后的差异miRNA和mRNA表达谱，对差异表达miRNA和共有差异表达mRNA进行关联分析，共匹配到1,009个潜在miRNA-mRNA对，从中进一步筛选出了95个相关的miRNA-mRNA对，最终证实了NDV感染引起下调表达的gga-miR-1648-5p与上调表达的PDE4B之间存在靶向调控关系，与此同时揭示了gga-miR-1648-5p/PDE4B作用对通过调控宿主细胞中NFKB等信号通路进而调控宿主TNF-α与IL-1β等促炎细胞因子的表达最终影响病毒感染的分子机制，为进一步阐明NDV与宿主间的相互作用提供了理论参考。