324HS1 exhibits strong enhancer activity specific to coordinate upregulation of Sprr genes. (A) Expression of Sprr2g in SP-1 cells increases with differentiation conditions. Relative levels of mRNA transcript are determined by when the amplicon crosses the threshold. (B) Expression of the Sprr genes, involucrin (Inv), Loricrin (Lor), and Klf4 in SP-1 cells under growth and differentiation conditions. Primer sequences and amplicon sizes are given in Supplemental Table III. (C) 324HS1–3 and 324HS1 have enhancer activity under differentiation conditions of SP-1 cells. All values are expressed relative to the activity of the minimal promoter. Activities represent the mean ±SEM of three experiments. (D) Multimerized 324HS1 (4×324HS1) has strong enhancer activity under differentiation conditions of SP-1 cells. The culture conditions are indicated on the x-axis. Activities represent the mean ±SEM of three experiments.
