Figure 5.

Delineating the active elements within the HS III K14 enhancer element. 320TKLuc was constructed to contain sequences −1,752 to −1,557 and −1,450 to −1,325 from the K14 upstream region. These sequences were introduced into the pLTK vector (10). Transfections were conducted with mouse keratinocytes (mK). Cell extracts were assayed subsequently for luciferase and β-gal values as described in Materials and Methods. Mutant plasmids contained the mutations as described in Fig. 4. After harvesting the cells, luciferase activities were determined and normalized against the β-gal values. Each experiment was repeated at least three times. Results shown are the averages of three experiments with standard deviations. The activity of the 320TKLuc was set at 100%.