Genes involved in AML1a-mediated expansion of hematopoietic cells. (A-B) BM cells infected with TetOFF-GFP-tetO-AML1a virus were sorted for GFP+ and cultured with SCF and IL-3. Sca-1⁺ cells in the presence (ie, without AML1a expression) or absence (ie, with AML1a expression) of Dox were used for expression microarray analysis. (A) Gene sets significantly enriched in Sca-1⁺ cells with AML1a expression compared with Sca-1⁺ cells without AML1a expression. Gene sets with FDR q < 0.25 among c2.v2. provided by the Broad Institute (http://www.broad.mit.edu/gsea) are presented in supplemental Table 1, among which gene sets related to hematopoiesis are presented along with net enrichment score (NES), FDR q-, and nominal (NOM) P values. (B) Enrichment plot for the gene sets (TAKEDA_NUP98_HOXA9_8D_UP and HSC_HSC_SHARED) and their corresponding heat maps showing genes in the leading edge. (C) Real-time PCR analysis to quantitate transcripts of the indicated genes in AML1a-expressing (Dox minus) cells relative to non–AML1a-expressing (Dox plus) cells. (D) Replating assays of AML1a-expressing cells infected with shRNA virus for the indicated genes. shRNA for luciferase served as a control. (E) Real-time PCR analyses to quantitate transcripts of the indicated genes after infection of the corresponding shRNA viruses. Results are presented as relative amounts of the transcripts compared with the control (ie, shRNA for luciferase). (F) Replating assays of AML1a-expressing cells infected with a dominant-negative form of Stat1. Vector-only infected cells served as a control. Representative data from at least 3 experiments are shown (C-F).