Mutations of the GATA-binding sites diminish the MBP P2 promoter activity. Jurkat cells were cotransfected with either pXP2-MBP containing a wild-type GATA-binding site, or pXP2-MBP containing a mutated GATA-binding site, bp −76 to −71, along with 10 μg of pEF-hGATA-1. The error bar represents the SEM for three independent experiments. Luciferase activity was normalized to β-galactosidase activity produced from a cotransfected CMV-βGal plasmid.