MicroRNA-21 Inhibit CVB3 Replication By Negative Regulatory Pathways Of PCBP1-p62/SQSTM1

Coxsackievirus B3(CVB3)is a common pathogen of viral myocarditis,pancreatitis and meningitis.Although CVB3 has been identified for more than half a century,there is no effective vaccine or therapy against this virus,mostly due to poorly understood interactions between CVB3 and the host cells which leads to the lack of drug targets.During CVB3 infection,various host cellular components,including proteins and non-coding RNAs,interact with the virus and affect viral infection.Our previous study demonstrated that a myocardium-enriched microRNA,mi R-21,is upregulated during CVB3 infection.However,the influence of mi R-21 on CVB3 infection remains obscure.Some studies have reported that microRNAs can regulate the expression of multiple genes.Other studies have found that CVB3 infection can not only induce cell autophagy,but also use its process to complete its own replication.Based on the above studies,we use He La cells as a model to detect changes in molecular levels in the host afterCVB3 infection,mainly using Western Blot,real-time fluorescent quantitative PCR,and dual luciferin reporter assay.The specific mechanism of the influence of various molecular changes on CVB3.Here,based on previous research reports that CVB3 infection upregulates mi R-21,first the bioinformatics method was used to predict the target of mi R-21 to be PCBP1.The dual luciferase reporter experiment identified PCBP1 as a direct target of mi R-21.Studies have found that CVB3 infection of He La can inhibit the expression of PCBP1 in cells,and overexpression of PCBP1 can promote CVB3 infection.Next,the effect of PCBP1 and CVB3 interaction on autophagy was discussed.By changing the level of PCBP1 protein,the changes of autophagy-related molecules were studied.The results of this study showed that the change of PCBP1 did not cause the change of LC3B;PCBP1overexpression reduced the p62/SQSTM1 protein Levels,but did not reduce its m RNA levels,indicating that PCBP1 regulates p62/SQSTM1 expression at the translation level.In addition,double luciferase reporter gene analysis confirmed that PCBP1 interacts with the 5'UTR of p62/SQSTM1,inhibiting its translation.This study revealed a new mechanism in CVB3 infection.Overexpression of PCBP1 inhibits p62/SQSTM1 protein expression and positively regulates CVB3 replication.Among them,mi R-21 in CVB3 infection mediates the decrease of PCBP1 and induces the antiviral effect of host cells.The mechanism of mi R-21-mediated PCBP1 in the process of CVB3 infection can provide new drug targets and research directions for the treatment of viral myocarditis caused by CVB3 infection.