Transcriptome analysis of GPs and the prediction of transcription factors downstream of IRF8. Gene expression profiling of fluorescence-activated cell sorter–purified Flt3⁺ and Flt3⁻ GPs from WT and Irf8^−/− mice was performed by microarray in biological duplicates. (A) Expression levels of transcription factor genes downregulated in Irf8^−/− GPs (false discovery rate <0.05; fold change >2) are displayed as a heat map. (B) Known DNA-binding motif analysis for the transcription factors depicted in (A) was performed in the 5 kb regions upstream of TSSs of the genes downregulated in Irf8^−/− GPs (false discovery rate < 0.05; fold change > 2) in comparison with all the other genes. The significance of the enrichment of DNA-binding motif instances was quantified by the Z-score.