TβRIII mRNA accumulates in CD34⁺ cells and in MEP in the absence of Gfi-1B. (A) Venn diagram showing the number of differentially expressed genes after Gfi-1B knockdown in CD34⁺ cells or MEP. shControl- or shGfi-1B–transduced cells were harvested 48 hours after retroviral infection, and mRNA were hybridized on Affymetrix microarrays. The number of genes differentially expressed as well as the number of genes that were up-regulated in both cell populations were indicated in the corresponding region of the diagram. (B) A subset of proteins involved in TGF-β signaling, which are up-regulated in both CD34⁺ and MEP after Gfi-1B depletion. The values represent Affymetrix data showing the fold increase between control and Gfi-1B knockdown cells. (C) Comparison of the mRNA expression of the 3 TGF-β receptors (TβRI, II, and III) in shControl- and shGfi-1B–transduced CD34⁺ or MEP. Quantitative RT-PCR was performed using TβRI, II, and III and Gfi-1B–specific primers. Data are expressed as fold change from controls, with GAPDH primers used as an internal control. Error bars represent SD of 4 experiments.