Combinatorial binding of heptad TFs is cell-type specific. (A) A composite graph with 3 components: (i) number of combinatorial binding peaks identified in the 4 cell types, for (ii) combinations of 2, 5, 6, and 7 heptad factors and (iii) heatmap showing z scores for the combinations presented in panel Aii. Star indicates combinations lacking GATA2 and/or TAL1. (B-C) UCSC browser tracks showing RPKM-normalized signal tracks of the heptad factors, H3K4me3, H3K27ac, H3K27me3, RNA-seq (public data: GSE75384), and IgG (control) in HSC-MPP, CMP, GMP, and MEP (left to right), at (B) the GATA1 locus (GRCh38 chrX:48,724,037-48,839,866), a gene vital for erythroid lineage specification, and at (C) the MPO locus (GRCh38 chr17:58,238,087-58,348,896), a gene specific to the monocytic lineage.