Fig. 4

Simultaneous expression of two foreign proteins by SCMV-based dual gene expression vectors in maize. a Schematic representation of dual-expression vectors: pSCMV-mCherry^P1/HC−Pro-GFP^NIb/CP and pSCMV-GFP^P1/HC−Pro-mCherry^NIb/CP. Foreign genes GFP and mCherry were individually inserted into either NIb/CP or P1/HC-Pro junction of the same vector to expect that GFP and mCherry could be simultaneously expressed from one SCMV vector. b Examination of GFP and mCherry expression in maize leaves systemically infected with SCMV-mCherry^P1/HC−Pro-GFP^NIb/CP and SCMV-GFP^P1/HC−Pro-mCherry^NIb/CP under confocal microscope at 7 dpi. Bars represent 20 μm. c and d Western blot analysis of GFP and mCherry accumulation in leaves systemically infected with SCMV-mCherry^P1/HC−Pro-GFP^NIb/CP (c) and SCMV-GFP^P1/HC−Pro-mCherry^NIb/CP (d). Total protein was extracted from infected leaves at 4, 7, 14, 21, and 28 dpi and subjected to western blot analysis with antibodies against GFP and mCherry. Coomassie Blue stained Rubisco is shown as a loading control