Antiviral Mechanism Research Of Host Long Non-coding RNA LncATV

Innate immunity is an important biological process that hosts against the invasion of and potential threat of the organism,involving multiple host molecules.After the virus infection,the virus can quickly stimulate the innate immune response of the body and induce the cell to produce a variety of cytokines,including interferon.There are three main types of interferon,including type ?,type ? and type ?,which can induce the expression of Interferon stimulated genes(ISG),these ISG proteins have many functions such as inhibiting virus infection,regulating innate immunity and other functions.It is also found that interferon can regulate noncoding RNA in cells and participate in a variety of biological processes.Long noncoding RNA(lncRNA)is a class of non-coding RNA with a length larger than 200 nucleotides.LncRNA can participate in the formation of chromatin in the nucleus with the action of DNA,or modulate the function of intracellular proteins or RNA.However,little is known about major functions of lncRNA.To study the changes in the IncRNA expression profiles regulated by interferon and the further screening of functional licRNA contribute to a deeper understanding of the mechanisms of interferon and the mechanism of the action of lncRNA.In this study,human hepatocellular carcinoma cell line Huh7 was treated with three different types of interferon.The expression profiles of IncRNA in cells were detected by gene chip,and the differential expression of lncRNA with three types of interferon up-regulation and down-regulation were screened.The screen finally obtained one of lncRNA,named long non-coding antiviral RNA(lncATV),which was induced by both interferon and virus.According to our research about the biological characteristics and functions of IncATV,lncATV was composed of only one exon and mainly located in the cytoplasm in Huh7 cells.We also found that knocking down IncATV can significantly inhibit multiple RNA viruses infection,including the hepatitis C virus(HCV),the zika virus(ZIKV)and Newcastle disease virus(NDV)and Sendai virus(SeV),and overexpression of lncATV can promote virus infection to some extent.After identifying the RNA virus,the host cells activate the innate immune response that promotes the production of interferon and pro-inflammatory cytokines,which inhibits the infection of the virus.In view of the effect of lncATV on various viral infections,we have detected the effect of IncATV on innate immune activation by the IFN-? and ISRE reporter system.The results show that knockouking down lncATV can significantly enhance the transcriptional level of IFN-? and the expression of the downstream interferon induced gene mediated by virus infection and active the innate immune response,while overexpression of IncATV significantly inhibits the innate immune response.To further determine the specific role of IncATV,we use IFN-(3 and ISRE reporter system,with knocking down IncATV and use different stimulants,to detect the effect of the reporter gene.It is found that when MDA5,MAVS and IRF3 are used as activators,knocking down IncATV has no obvious effect on the activity of the reporter gene,while it is significant activated by RIG-I.Knocking down IncATV in RIG-I function deficient Huh7.5.1 cells that does not affect the infection of virus,while after knocking down IncATV in the Huh7 cells,the virus can be significantly inhibited.The antiviral activity of lncATV can be weakened to a certain extent by using siRNA to knock down the endogenous RIG-I.The above results indicate that RIG-I plays an important role in IncATV antiviral process.In summary,we have studied the expression profiles of lncRNA induced by three types of interferon,and screened a lncRNA that affects a variety of RNA virus infection,named as,lncATV.lncATV inhibits the activation of RLR and IFN-?signaling pathways by interfere the activation of the pattern recognition receptor RIG-I and negative regulate the innate immune response.These studies further enrich understanding of the mechanism of interferon function,reveals a new molecular mechanism that lncRNA participates in the regulation of innate immunity and provides potential targets for the prevention and control of viral infection.