Figure 3.

Effects of configuration around the HS2 region on the enhancer activity in stable transformants. (A) Luciferase assay using stable transformants. Mixtures of stable transformants containing 10–20 different clones of each construct were collectively assayed for luciferase activities and the relative light units (RLUs) adjusted with total protein amounts were shown in the graph. (B) The relative luciferase activities of stable transformants normalized relative to the copy number of the integrated plasmid DNA. Five clones from each construct were subjected to Southern blot analysis to determine the relative copy number of the integrated plasmid DNA, which was used for correcting luciferase activities. A ³²P-labeled luciferase cDNA fragment was used as a probe. The averages and the standard deviations are shown above. P values against HS2 constructs were assessed by student’s t-test.