Inhibition of Autographa californica nucleopolyhedrovirus (AcNPV) polyhedrin gene expression by DNAzyme knockout of its serine/threonine kinase (pk1) gene.

DNAzyme is known to selectively cleave RNA at predetermined site. Transfection of Autographa californica nucleopolyhedrovirus (AcNPV) infected Sf9 cells with serine/threonine kinase (pk1) mRNA specific DNAzymes, DZ1 and DZ2 to cleave the viral coded (pk1) mRNA in between 87th and 88th, and 250th and 251st nucleotide, respectively inhibited the pk1 mRNA and its protein expressions. Interestingly, polh mRNA and protein expressions were also inhibited by these DNAzymes despite their inability to cleave polh mRNA. The polyhedrin promoter driven green fluorescent protein (GFP) mRNA and protein expressions were also inhibited by these pk1 specific DZs. Surprisingly the extents of inhibition of polyhedrin and GFP at different concentrations of both DZs were higher than that of pk1 mRNA and protein expressions. These results suggested that pk1 regulates polyhedrin promoter driven transcription of AcNPV, and the effect of one gene expression on that of other can be studied by DNAzyme knockdown.