Reverse genetics systems are powerful tools for functional studies of viral genes or for
vaccine development. Here, we established
DNA-launched reverse genetics for the pestivirus Bungowannah virus (BuPV), where
cDNA flanked by a
hammerhead ribozyme sequence at the 5' end and the
hepatitis delta ribozyme at the 3' end was placed under the control of the CMV
RNA polymerase II promoter. Infectious recombinant BuPV could be rescued from pBuPV-
DNA-transfected SK-6 cells and it had very similar growth characteristics to BuPV generated by conventional
RNA-based reverse genetics and wild type BuPV. Subsequently,
DNA-based ERNS deleted BuPV split genomes (pBuPVāERNS/ERNS)-co-expressing the ERNS
protein from a separate synthetic CAG promoter-were constructed and characterized in vitro. Overall,
DNA-launched BuPV genomes enable a rapid and cost-effective generation of recombinant BuPV and virus mutants, however, the
protein expression efficiency of the
DNA-launched systems after transfection is very low and needs further optimization in the future to allow the use e.g., as
vaccine platform.