Expression of GFP and DsRed from an artificial polycistronic transcript after treatment with anti- gfp and anti- DsRed PNA. (A) Structure of the artificial gfp/DsRed-operon with the antisense target sites indicated by a small arrows. (B) Relative amounts of GFP (left panel) and DsRed (right panel) in cells after treatment with increasing concentrations of anti-gfp (top), anti-DsRed (center) and controls consisting of anti-lacZ and anti-lacY PNAs (bottom). For treatment with anti-gfp and anti-DsRed PNAs, squares and triangles represent values for two different antisense sequences that share genetic targets. For the control experiments, squares represent treatment with anti-lacZ PNA and triangles treatment with anti-lacY PNA. All data points are derived from six double samples using non-treated cells as standard and pGRFPsep-free cells to remove background fluorescence.