Dynamic epigenetic enhancer signatures are predictive for key transcriptional regulators associated with cellular differentiation states. Homo sapiens

Cellular differentiation is orchestrated by lineage-specific transcription factors and associates with cell type-specific epigenetic signatures. Here, we utilized stage-specific, epigenetic "fingerprints" to deduce key transcriptional regulators of a cellular differentiation process. In the model of human macrophage differentiation, we globally mapped the distribution of epigenetic enhancer marks (histone H3 lysine 4 monomethylation, histone H3 lysine 27 acetylation, and the histone variant H2AZ) and show that cell type-specific epigenetic "fingerprints" correlate with specific, de novo derived motif signatures at all differentiation stages studied (hematopoietic progenitor cell, monocyte, macrophage). We validated the novel, de novo derived, macrophage-specific enhancer signature which included ETS, CEBP, bZIP, EGR, E-Box and NFkB motifs by ChIP-sequencing for a subset of motif corresponding transcription factors (PU.1, C/EBPbeta, and EGR2) which confirmed their predicted association with differentiation-associated epigenetic changes. This study highlights the power of genome-wide epigenetic profiling studies to reveal novel functional insights. It describes the dynamic enhancer landscape of human macrophage differentiation and provides a unique resource for macrophage biologists. Overall design: ChIP-seq of 3 histone marks and 3 transcription factors in human blood monocytes and macrophages