Novel microRNAs and targets prediction in PRRS virus genome

In this paper, 4 microRNAs and their targets were predicted through a de novo prediction procedure in the genome of Porcine Reproductive and Respiratory Syndrome virus. Through clustalW analysis, these 4 microRNAs were recognized as novel PRRSV derivate microRNAs. Target prediction results showed PRRSV mir-1, 2 and 4 have total 16 targets in porcine 3' UTR database. These targets could be divided into 4 groups, which related to germ cell development, immunity function, apoptosis and other cell function genes, respectively. The roles of these targets inhibition on virus infection were issued and the link of these suppressions to clinical syndrome was discussed. In conclusion, the results showed microRNAs were exploited by PRRSV to escape host anti-virus surveillance and help virus infection, and the consequences of individual target suppression were related closely to clinical syndromes. In conclusion, the results will deep the understanding on PRRSV infection and provide novel virus microRNAs as targets for counter virus infection in gene therapy era.