Heatmap showing temporal expression of subset of Hoxa9-regulated genes closely associated with Hoxa9 and Meis1 binding sites. A subset of genes are shown that are significantly differentially expressed over the 120-hour period after 4-OHT withdrawal (FDR P < .05 and median fold change > 1.5) compared with controls. Data are normalized across samples such that the expression value of each individual gene has zero mean and SD of 1. Many of the up-regulated genes shown have been directly implicated in leukemogenesis in both human studies and animal models (see text). Many of the down-regulated genes are involved in myeloid differentiation. Heatmaps of the entire set of differentially regulated genes are provided in supplemental Figure 4, and additional information on statistical analysis is provided in supplemental Data.