FIGURE 3.

Putative E-boxes enhance SelW promoter activity in differentiating C2C12 cells. A, schematic illustration of SelW promoter fragments. Four putative E-boxes are present in the promoter region from −973 to −240 bp, and the reporter plasmid constructs used in the luciferase analysis are shown (upper panel). DNA sequences in each E-box are shown in the lower panel. B, SelW promoter activity in C2C12 cells using a deletion mutant after 1 day of culture in DM. C2C12 cells were transfected with SelW promoter reporter plasmids (−973SelW/Luc or −240SelW/Luc) and pRL-TK. After cultivation up to ∼100% confluence in GM, the cells were cultured in DM for 1 day. SelW gene promoter activity was measured and normalized to the Renilla activity of pRL-TK. Results are expressed as means ± S.D. of three independent experiments performed in triplicate.