Fig 5.

 Hormone responsiveness of pIE1 and pIE2 enhancers is abrogated by mutation of the hormone response elements (HREs). (A) Substitutions were introduced into each of the half-sites (underlined) in wild-type pIE1 and pIE2 HREs. The sites of these mutations are shown in bold. (B) T-47D cells were transfected with pGL3-Promoter luciferase-reporter plasmids driven by either the wild-type pIE1 enhancer (pIE1), pIE1 containing mutation of HRE1 (pIE1mut), the wild-type pIE2 enhancer (pIE2), or pIE2 containing mutation of HRE2 (pIE2mut). Cells were treated with vehicle or 10-nM R5020. (C) A549 cells were transfected with pGL3-Promoter luciferase-reporter plasmids driven by either the wild-type pIE2 enhancer (pIE2) or pIE2 containing mutation of HRE2 (pIE2mut) and treated with either vehicle or 10-nM dexamethasone. After 24 hours, cells were collected for assay of luciferase activity. The data are expressed as fold induction over untreated cells. Each bar represents the mean ± SEM of 3 independent experiments