Regulatory regions with cell-type-specific heptad occupancy have distinct epigenetic features. (A) A Uniform Manifold Approximation and Projection (UMAP) depicting the result of clustering 85 100 accessible regions in HSPCs annotated with ChIPmentation/ChIP-seq signal strengths using the Louvain algorithm. (B) Individual violin plots of log normalized signal derived from ATAC, 3 histone marks (H3K27ac, H3K4me3, and H3K27me3), and CTCF, accompanied by a bar plot showing the number of regions in each cluster. Intercluster signal variability allows annotation of individual clusters based on their regulatory potential. (C) UMAPs overlaid with ChromHMM annotation of 85 100 individual regions show striking similarity to annotations shown in Figure 6B. (D) UMAPs colored based on log2 fold change of binding of the heptad TFs in pairwise comparisons between GMP and MEP. MEP- and GMP-specific enrichment of TF binding is identified, and borders demarcated by dashed lines: black (enriched in MEP) or gray (enriched in GMP). (E) Signal of PU.1 in dendritic cells (DC) (GSE58864) across the clustered regions. PU.1 signal enrichment in dendritic cells mirrors heptad factor enrichment patterns in GMP. (F) Signal of GATA1 in proerythroblasts (ProE) (GSE36985) across the clustered regions. GATA1 signal enrichment in proerythroblasts mirrors heptad factor enrichment patterns at these regions in MEP.