An ~55% reduction was observed on the −109 to +247 fragment under the same conditions (2.9 vs. 6.5 fold change). In comparison, dexamethasone treatment was unable to exert a significant influence on ponasterone A activation in the 293-EcR cells, with only an ~26% reduction in activity observed on the −1652 to +247 fragment (5.1 vs. 6.9 fold change) and an ~6% reduction observed on the −109 to +247 fragment (46.1 vs. 49.1 fold change). Treatment with dexamethasone alone did not cause repression of promoter activity in the 293-EcR cells. Neither ponasterone A nor dexamethasone exerted a significant effect on the SEPP1 promoter constructs in HEK-293 cells.
