Decreased tal1 expression levels impair murine adult hematopoiesis. (A) Lentiviral construct for murine shRNAtal1 as in Figure 1. (B) Western blot analysis of TAL1 protein in shRNActrl and shRNAtal1 transduced MEL cells. (C) Transduced Sca1⁺ cells were plated in semisolid culture and the colonies issued from shRNActrl and shRNAtal1 transduced (GFP⁺) and nontransduced (GFP^–) clonogenic progenitors were counted. Each symbol represents an independent experiment. (D) At 1, 3, and 6 months after Sca1⁺ cell transplantation, engraftment levels in the peripheral blood of treated mice were determined by the percentage of GFP⁺; the horizontal bars indicate the median % of GFP⁺ cells. (E) Percent of GFP⁺ myeloid (CD11b), B-lymphoid (B220) and T-lymphoid (CD3) cells in the blood of 3-month shRNActrl and shRNAtal1 mice.