Effects of C/EBPα on 32Dcl3 cells. (A) Schematic diagram of wild-type (p42) and C/EBPα mutants. (B) Levels of ectopic C/EBPα in retrovirally transduced 32Dcl3 cells. Morphology of 32Dcl3 cells (C, upper panels) and lineage-negative bone marrow cells (C, lower panels) retrovirally transduced with either p42, Lys298Glu, Δ 177-191, BRM-2, p30 C/EBPα, or the empty MigR1 vector. Cells were selected for GFP positivity and treated for 3 days with G-CSF (C, upper panels) or cultured for 7 days in a cocktail of cytokines without G-CSF (IL-6, Flt3/Flk2 ligand, SCF, GM-CSF, and IL-3) (C, lower panels). Original magnification, × 40.