We examined regulation of the human erythropoietin (Epo) gene through the GATA sequence in the Epo promoter, and demonstrated that Hep3B and HepG2 cells express human GATA-2 (hGATA-2) mRNA and protein. Nuclear extracts of QT6 cells transfected with hGATA-1, -2 or -3 transcription factors revealed specific binding to the GATA element in the human Epo gene promoter by gel mobility shift assay. Transient transfection of Hep3B cells with hGATA-1, -2 or -3 demonstrated that each of these transcription factors significantly decreased the level of expression of Epo mRNA as assessed by a competitive polymerase chain reaction. Furthermore, transient transfection of Hep3B cells with hGATA-1, -2 and -3 and an Epo reporter gene construct showed significant inhibition of the Epo promoter. We conclude that the hGATA-1, -2 and -3 transcription factors specifically bind to the GATA element in the human Epo gene promoter and negatively regulate Epo gene expression.
- Erythropoietin gene expression
- GATA transcription factor
- Reporter gene
- Transient transfection