Reverse Genetics for Porcine Reproductive and Respiratory Syndrome Virus.

Porcine reproductive and respiratory syndrome (PRRS) is a reemerging swine disease, and has become economically the most significant disease in pork production worldwide. The causative agent is PRRS virus (PRRSV), which is a member virus of the family Arteriviridae. The PRRSV genome is a single-stranded positive-sense RNA and is infectious. Two strategies in the PRRSV reverse genetics system have been employed for reconstitution of progeny virus: RNA transfection and DNA transfection. The PRRSV reverse genetics has broadly been used for studies including protein structure-function relationship, foreign gene expression, vaccine development, virulence determinants, and viral pathogenesis. Herein, we describe the modification of the pFL12 "RNA launch" reverse genetic system to the CMV promoter-driven pXJ41-FL13 "DNA launch" system. The generation of progeny PRRSV using pXJ41-FL13 is further elucidated.