Changes Study In MiRNA Expression Profiles In PK-15 Cell Infected With Porcine Epidemic Diarrhea Virus And Preliminary Study Of Its Impact On Virus Replication

Porcine epidemic diarrhea (Porcine Epidemic Diahorrea, PED) caused by Porcine epidemic diarrhea virus (Porcine Epidemic Diahorrea Virus, PEDV) is a intestinal infectious disease. Currently, there is no effective treatment and therapy can be treated on the PED. One of the control and prevention main way to PED is vaccination. However, recent research have shown that some farms still broke PED after used vaccination. Therefore, find more effective means of prevention and treatment of PED is very important.MiRNA is a class of small non-coding RNA. MiRNA acted widespread, could regulate the growth, differentiation, nmetabolism, apoptosis and other important life processes of cells. With further research, more miRNAs were found that had antiviral function, and the miRNAs was able to be used for the conserved sequences of viral gene, so miRNA has antiviral activity to the different strains of the same virus.To explore the function of porcine epidemic diarrhea virus in changing miRNA expression profiles in porcine kidney 15 cell line(PK-15), total RNAs from Porcine Epidemic Diahorrea Virus(PEDV) infected PK-15 cells were extracted and then subjected to solexa sequencing, bulid miRNA expression profiles of infected and normal samples, and difference analysis. The results showed that 214 miRNAs displayed signifycant differential expression between infected and normal samples, of these,175 were significantly up-regulated and 39 were significantly down-regulated. Real-time quantitative PCR (RT-qPCR) experiments were preformed for 10 significantly differentially expressed miRNAs of the two samples, and agreement was found between the sequencing and RT-qPCR data.To explore differentially expressed miRNAs how to effect on proliferation of the virus, bind to the target gene prediction, miRNA expression profiling and those miRNAs what had been reported with the immune-related miRNA, this experiment selected ssc-let-7f and other 6 miRNAs to synthesis miRNA minics and transfected into PK-15 cells that had inoculated PEDV, sampling to carry on quantitative PCR, observe the changes of PEDV’s the amount, verify each miRNA viral proliferation. The results showed that ssc-let-7f at 12h,24h and 36h were all significantly different, showed that ssc-let-7f was able to suppression PEDV infection on a certain extent.To our knowledge, this is the first report of expression analysis of PK-15 cells miRNAs after exposure to PEDV. Our results suggest that elucidation of the molecular mechanisms responsible for miRNA regulation of the host’s innate immune system should help with the development of new control strategies to prevent or treat PEDV in fections in pig. This study also can provide new ideas for further reveal anti-viral mechanism of miRNA, and provide theoretical reference for extensive research PEDV pathogenesis.