ChIP-seq analysis of chromatin state plasticity in primary human adult erythroid progenitor cells

We report a computational approach for investigation of chromatin state plasticity. We applied this approach to investigate an ENCODE ChIP-seq dataset profiling the genome-wide distribution of H3K27me3 in 19 human cell lines. We found that high plasticity regions (HPRs) can be divided into two functionally and mechanistically distinct groups, consisting of CpG island proximal and distal regions. We identified cell-type specific regulators correlating with H3K27me3 patterns at distal HPRs in ENCODE cell lines. Furthermore, we applied this approach to investigate mechanisms for poised enhancer establishment in primary human erythroid precursors. We predicted and validated a previously unrecognized role of TAL1 in modulating H3K27me3 patterns through interaction with additional cofactors, such as GFI1B. Our integrative approach provides mechanistic insights into chromatin state plasticity and is broadly applicable to other epigenetic marks.