The EKLF-GATA1 fusion proteins regulated hemoglobin protein expression in CD34⁺ cells. (A) CD34⁺ bone marrow cells were transduced with vector expressing EKLF, GATA1, EKLF-GATA1 (EG), or vector only. Cells were harvested 7 days after transduction and cell lysates subjected to Western blotting analysis. Samples containing 50 μg (for γ-globin, δ-globin, and β-actin) or 5 μg (for *β-globin) of protein were electrophoresed, transferred to nitrocellulose, and probed with antibodies directed against γ-, δ-, or β-globin or β-actin. β-Actin served as an internal control. (B) Graphical representation of data in panel A (normalized to the β-actin) measured by densitometry to indicate the fold increase in globin protein expression over vector only–transduced cells. *P < .05 versus vector only–transduced cells. Error bars indicate SD of the mean of 3 independent experiments.