Fig. 2

Characterization of the ER-α response sequence in the apoM gene promoter. a Luciferase reporter assay for the apoM promoter. A series of truncated apoM promoter-reporter constructs were schematized. Each promoter-reporter construct or the promoter-less plasmid pGL3-basic was co-transfected with ER-α expression plasmid into MCF-7 cells. After 24 h of transfection, the cells were lysed and measured for firefly and renilla luciferase activities. The luciferase activity of each construct was presented relative to the pGL3-basic activity. b Mutation analysis of the ER-α binding site. Luciferase activity expressed by the ER-α site-directed mutant relative to pGL3-basic activity. c Compared with the existing information in human genome database, the DNA sequence of the mutation contains a mutation region, from −1580 to −1575 upstream from the transcriptional start site