Repression by hnRNP-K of the CD43 promoter present within an extrachromosomal plasmid.

Eight micrograms of the luciferase reporter construct p43Wt were transfected into K562 cells mixed with either 16 μg of full-length hnRNP-K, which expresses hnRNP-K, or 16 μg of its parent vector empty of hnRNP-K–coding sequences. One microgram of the β-galactosidase expression plasmid pRSV-β was also included in each transfection to control for transfection efficiency. Transfected cells were treated with PMA for 12 hours and harvested and luciferase and β-galactosidase assays performed. The levels of β-galactosidase activity were taken as reflective of transfection efficiency and used to correct the luciferase assay results. Depicted as histograms are the levels of luciferase activity directed by p43Wt divided by those directed by the empty vector pATLuc in the presence of full-length hnRNP-K (+hnRNP-K) or the equivalent empty vector (−hnRNP-K). The means of these levels ± SD resulting from 3 independent experiments are displayed.