HOXA10 binds with high affinity to Hlf, Dkk1, and Gata-1. Lin− rtTA-HA10 bone marrow cells were cultured in 0 or 0.5 μg/mL doxycycline and the expression of (A) HOXA10, (B) Dkk1, (C) Gata-1, and (D) Hlf was quantified by Q-RT-PCR 2 hours, 6 hours, and 16 hours after induction and compared with the value of 0 μg/mL doxycycline sample at each time point; n = 3; *P < .05. (E) Shown are the products of the amplified 5′ cDNA ends from Lin− bone marrow cells for each gene that was sequenced. (F) Using the sequences from panel E, we identified possible binding sites for HOXA10 in the promoter region of Dkk1, Gfi-1, Hlf, and in the intron-1 of Gata-1. (G) EMSA showing the sequences from panel F as competitors to binding of HOXA10 in nuclear extracts from induced transgenic lineage-negative cells to a known HOXA10 probe in 100- and 300-fold excess of unlabeled duplex oligo-nucleotide. (H) Luciferase assay in HeLA cells transfected with 100 or 300 ng HOXA10 expression plasmid reveal induction of luciferase when driven by promoter regions for Dkk1 and Gfi-1. Increasing concentrations of HOXA10 expression results in increasing luciferase activity. The luciferase values were normalized to Renilla, used as an internal transfection control to assess relative intensity (RI) (n = 6). Data represent mean ± SD.