FIGURE 3.

A highly conserved CRE is critical for RGS2 promoter activity. PGL3 basic luciferase reporter vectors containing −4367, −867, −367, −117, and −47-bp RGS2 promoters (A), −867 bp WT or mutant RGS2 promoters (D), and −4367 bp WT or mutant RGS2 promoters (E) were co-transfected with pRL-SV40 vector in rabbit aortic VSMC. Cells were then incubated (6 h) with FSK (10 μm) or vehicle (Veh) (Me₂SO₂). RGS2 promoter activity was analyzed by dual-luciferase assay and then normalized to pGL3 vector (A) or to WT basal (D and E). Two putative CREB binding sites, CRE1 and CRE2, were predicted in the −4367 bp mouse RGS2 promoter (B). Four key nucleotides in the RGS2 CRE1 and CRE2 sequences were subjected to site-directed mutagenesis (C). Data are represented as mean ± S.E. of at least six independent experiments. ***, p < 0.001 versus pGL3. ††, p < 0.01 versus −4367 bp basal.