Transcriptional activation by MLL-ELL.

A luciferase reporter gene under control of HoxA7 upstream sequences (pGL3-HoxA7) was cotransfected into 293T cells with expression constructs encoding MLL5′ or various MLL-ELL fusion cDNAs. Luciferase activity was corrected for transfection efficiency based on the activity of a cotransfected β-galactosidase expression construct. The transcriptional activating potential for each MLL construct is expressed as the fold-induction relative to pMSCVneo. Bars represent the mean ± SD of 3 independent transfection experiments.