Figure 2.

Expression of the luciferase reporter gene is driven by the different derivatives of the minimal Hcrt promoter. Luciferase signals from transiently transfected parental 293 (A, light green bars) and ebf2-lentiviral-transduced 293 cells (293-ebf2, B, dark green bars) showed that the expression of luciferase was driven by the different Hcrt promoter sequence derivatives. (B) Overexpression of ebf2 increased the activity of secreted luciferase. Mutations introduced to the proximal olf-1 site (D1 and M1 groups) increased, whereas mutations of the distal olf-1 site (D2 and M2) decreased the expression of luciferase, compared with that in the WT promoter sequence in parental 293 cells. In 293-ebf2 cells, deletion of the proximal site increased luciferase expression, whereas the other mutations caused no statistically significant changes, although trends similar to those observed in parental 293 cells were observed. *P<0.01 (analysis of variance and Holm-Sidak post-hoc test) vs. groups indicated by joining lines. n=8 experiments/group. WT, wild-type; D, deletion; M, mutation; ebf2, early B-cell factor 2; IFN, interferon; PAR, parental.