Fig. 3

Transcriptional up-regulation of the Slug gene by Sox4. a Left: Hec6 cells were transfected with Slug reporter constructs, together with Sox4, Sox7, and Sox9, respectively. Relative activity was determined based on arbitrary light units of luciferase activity normalized to pRL-TK activity. The activities of the reporter plus the effector relative to that of the reporter plus empty vector are shown as means ± SDs. Right: analysis of mRNA levels for the Slug gene with total RNA extracted from Hec6 cells after transfection of Sox4, Sox7, and Sox9 using real time RT-PCR assays. The experiment was performed in triplicate. b The Slug promoter sequence containing four putative Sox4-binding sites including Sox4-1, Sox4-2, Sox4-3, and Sox4-4 sites. c, d Various promoter constructs were used for evaluating transcriptional regulation of the Slug promoter by Sox4, Sox7, and Sox9. The experiment was performed in triplicate. e ChIP assay data showing that Sox4 is bound to Slug promoter regions, in particular after culturing in STK2 for 3 days