FIGURE 3.

GFP expression imaging in Arabidopsis thaliana protoplast. (A) Confocal microscope was used to image the Arabidopsis thaliana protoplast incubated with DNA only as a negative control, PEG/Ca²⁺ as a positive control, PDMAEMA + DNA (N/P ratio of 15:1), and PEI + DNA (N/P ratio of 15:1). GFP fluorescence images were captured with 488 nm laser excitation and 539 nm emission wavelengths. Chlorophyll autofluorescence images were captured with 633 nm laser excitation and 691 nm emission wavelengths. Scale bar, 20 μm. Protoplasts were incubated with PEG/Ca²⁺ for 15 min and washed with W5 solution to remove PEG. Then, protoplasts were resuspended with W5 solution in a 1.5-mL tube for another 12 h in the dark. The protoplasts were incubated with PDMAEMA + DNA or PEI + DNA directly for 12 h. (B) Western blot of the GFP expression level of Arabidopsis thaliana protoplasts incubated with DNA only, DNA-PEG/Ca²⁺, PDMAEMA + DNA, and PEI + DNA.