As expected, consensus motifs of known key regulators are over-represented in corresponding facet-specific enhancers, for instance ETS, C/EBP, and NF-κB in monocyte-specific enhancers, RFX and SOX in neurons, and HNF1 and HNF4a in hepatocytes (Supplementary Fig. 23). Notably, the AP1 motif appears to be enriched across all facets, perhaps associated with a general role for AP1 in regulating open chromatin19.
