38th Annual Meeting of the Society for Invertebrate Pathology

The availability of plasmids containing infectious densovirus (DNV) genomes and of DNV transcription maps has prompted research into their potential as expression vectors. A series of non-infectious vectors derived from the Junonia coenia densovirus (JcDNV) have been constructed expressing non selectable (lacZ) or selectable markers (neo, gfp) inserted in frame into the VP gene under control of the P9 promoter. By transfecting these constructs to lepidopteran cell lines, cell clones stably expressing the transgene could be produced. Analysis of transformed cells revealed that the JcDNV sequence was integrated into the host cell DNA and that the 5’ inverted terminal repeat region was the primary site of recombination. Other JcDNV-derived constructs were made expressing genes of interest such as human eythropoïetin and human γ interferon. Sf9 cell clones constitutively expressing these genes were obtained and the biological activity of recombinant proteins was demonstrated. By microinjecting Drosophila melanogaster preblastoderm eggs with a JcDNV-derived plasmid expressing the lacZ gene, high β-galactosidase expression was observed in somatic tissues throughout ontogenesis, from larvae to adult flies. JcDNV-derived vectors thus appear as interesting tool for somatic transgenesis. Taken together these results demonstrate the flexibility and reliability of using densovirus-derived vectors for multiple biological applications.