FIG. 5.

Interaction of the cGRE/negative element and the serum response region. The PLF serum response region from – 234 to – 204 alone (SR), the serum response region with the cGRE/negative element (– 256 to – 204, designated cGRE-SR), and the serum response region with the cGRE/negative element separated by an additional 5 bp were fused to the herpes virus thymidine kinase minimal promoter. These DNAs were transfected into mouse L cells, which were then maintained for 2 days in 0.5% or 15% serum. Conversion of chloramphenicol to acetylated forms in 0.5% serum (–) and 15% serum ( + ), respectively, was 4.1% and 91.3% for – 234/– 204; 0.5% and 6.6% for – 256/– 204; and 3.0% and 61.9% for – 256/– 204 ( + 5 bp).