Figure 2.

PSF-SOD1 has a higher cell-permeable ability than TAT-SOD1. (a) PEN analogs PSF, PCR, and PCN fused with SOD1 were expressed, purified, and detected by Coomassie brilliant blue staining (upper panel) and Western blot (lower panel). (b) SOD enzyme activity was measured according to the manufacturer's instructions. (c, d) Western blot analysis for cell permeability of fused SOD1 proteins. (e) Immunofluorescence analysis for cell permeability of fused SOD1 proteins with SOD1 antibody (green) and counterstained with Hoechst (blue). ^∗∗∗p < 0.001 compared with TAT-SOD1-treated cells.