Distinct binding syntax of the DFREs. Enrichment of ChIP-seq TFBSs in T cells (A) and hESCs (B). The heatmap on top illustrates enrichment/depletion significance (−log10 binomial test P) in DFREs, SLrs, and ENrs compared with all DNase-seq and H3K27me3 ChIP-seq peaks in the corresponding cell type. The red and blue shades represent significance levels of enrichment and depletion, respectively. (C) Functional specificity of silencer and enhancer TFBSs in these DFREs. According to their activity in T cells and H1 hESCs, these TFBSs are categorized into two groups: function specific (i.e., unique to one cell type) and shared (i.e., shared by two cell types). The numbers in the bars are the average numbers of TFBSs per DFRE. (D) Distribution of silencer TFBSs (the blue bars and line) and enhancer TFBSs (the orange bars and line) in DFREs. (E) Distance of silencer TFBSs to their nearest enhancer TFBSs. The background distribution was generated through randomly scattering silencer and enhancer TFBSs within DFREs.
