Fig. 1

Expression of C-EGFP fusion protein in PK15 cells. a Plasmids pEGFP-N1-C and pEGFP-N1 were transiently transfected and cells were lysed at 24 hpt and 48 hpt. Western blot analysis was performed with mouse anti-EGFP and mouse anti-tubulin primary antibodies, and HRP-conjugated goat anti-mouse IgG secondary antibody. Tubulin was used as control. Protein marker is shown on the right. b PK-15 cells transfected with plasmids pEGFP-N1-C or pEGFP-N1 were observed under a fluorescence microscope at 24 hpt. Scale bar, 100 μm. c Schematic representation of C-EGFP protein and its cleaved form. Black frame represents C protein and green frame represents EGFP protein. The arrow indicates the cleavage site of C protein between residues A255 and V256 by SPP. Cleaved form of the fusion protein contains 12 residues at C-terminal of C protein and EGFP protein. Amino acid sequence of C protein of CSFV strain Shimen starting with S169 and ending with A267 is exhibited