Fig. 3.

Analysis of biological activity of recombinant TAT:SOX2 and TAT:OCT4 proteins. a HEK-293T/17 cells were co-transfected with 6xO/S-Luc luciferase reporter plasmids along with Oct4 or Sox2 or Oct4 and Sox2 expression vectors. 6xO/S-Luc and TK-Luc reporter plasmids were used to conform the promoter specificity and system sensitivity, respectively. Untransfected cells were treated as negative control. After 24 h of transfection, cells were harvested and luciferase assays were performed. Relative luciferase activity of each treatment is shown, which is normalized to that of 6xO/S-Luc control (given as 1.0). b HEK-293 cells were transfected with 6xO/S-Luc luciferase reporter plasmids. Negative control was untransfected cells. After 24 h of transfection, cells were incubated with 40 nM TAT-Oct4 and 40 nM TAT-Sox2 in serum-free medium for 3 h. Then harvested cells and performed luciferase assays. Relative luciferase activity of each treatment is shown, which is normalized to that of 6xO/S-Luc control (given as 1.0)