Figure 4.

Real-time RT-PCR and Western blots for SUMO1 with and without SUMO1 siRNA transfection in fibroblasts. Three SSc fibroblast strains (two with anti-topo I and one with anti-RNA polymerase III positive serum) were transfected with SUMO1 siRNA. After 48-hour transfection, total RNAs were used for measuring SUMO1 transcript levels (Figure 4a), and the nuclear extracts were used for measuring SUMO1 protein (Figure 4b). Error bars indicate standard deviation.