Fig. 3.

Enhancer activity of miR 144/451 preCRMs. (A) Design of the reporter construct. PreCRMs were positioned upstream of a γ-globin gene promoter linked to a firefly luciferase cDNA. The bent arrow indicates the start of the luciferase open reading frame. (B) Luciferase activities, reported as the fold increase over that of the parent plasmid, are shown from three separate transient transfection experiments, represented as separate bars. Error bars indicate standard deviation from quadruplicate luciferase determinations from a single experiment. Reporter assays were performed in human K562 erythroleukemia cells and in MEL cells treated with HMBA to induce erythroid maturation. Firefly luciferase activities are normalized to Renilla luciferase activities expressed from a cotransfected control plasmid. The DNA segment Zfpm1R13 is a positive control for a known enhancer (30).