Development of new potato virus X-based vectors for gene over-expression and gene silencing assay

- A 35S promoter-driven infectious clone of PVX, pCaPVX100, was constructed.
- Vector pCaPVX440 can express two foreign genes at the same time.
- Plasmid pCaPVX760 can express foreign gene through gene substitution strategy.
- Gene silencing vector pCaPVX440-LIC contains a ligation independent cloning site.

Multiple plant viruses, including potato virus X (PVX), have been modified as vectors for expressing heterologous genes or silencing endogenous genes in plants. PVX-based vectors facilitate the functional analysis of genes in plant. However, they can only express one protein in a time. In this paper we report the construction of new vectors based on a 35S promoter-driven PVX infectious clone, pCaPVX100. Vector pCaPVX440 contains two additional subgenomic promoters and can be utilized to express two foreign genes at the same time. Plasmid pCaPVX760 is a CP minus vector and can be used to express foreign proteins through the gene substitution strategy. In addition, plasmid pCaPVX100 was engineered into a gene silencing vector (pCaPVX440-LIC) by introducing a ligation independent cloning (LIC) site into the vector. These results indicate that the newly developed PVX vectors are competent for multiple research purposes.