Figure 4.

Activation of the FGF-2 gene promoter by growth factors, forskolin, and PMA in astrocyte cultures. Human astrocytes (QG) were transfected with a luciferase reporter plasmid containing a −1800/+314-bp fragment (relative to the transcription start site) of the FGF-2 promoter. Treatment with growth factors, forskolin, or PMA was for 24 h in serum-free medium at the concentrations given in Figures 1 and 2 as described in MATERIALS AND METHODS. Bar graphs represent mean ± SEM from 6–15 samples obtained in two experiments. Analysis of variance showed an overall significant effect of treatments on luciferase expression (p < 0.000002). Luciferase expression was significantly increased in astrocytes treated with PMA (p < 0.00001), FGF-2 (p < 0.0005), IL-1β (p < 0.05), or EGF (p < 0.005).