PLX011575

GSE74999: HDAC inhibitors cause site-specific chromatin remodeling at PU.1-bound enhancers in K562 cells

• Organsim human
• Type RNASEQ
• Target gene
• Project ARCHS4

We used the myelogenous leukemia line K562 as a model of HDACi-induced differentiation to investigate chromatin accessibility (DNase-seq) and expression (RNA-seq) changes associated with this process. We identified several thousand specific regulatory elements (~10% of total DHS sites) that become significantly more or less accessible with sodium butyrate or suberanilohydroxamic acid (SAHA) 72-hour treatments. Most of the differential DNase-hypersensitive (DHS) sites display hallmarks of enhancers; including being enriched for non-promoter regions, associated with nearby gene expression changes, and capable of increasing luciferase reporter expression in K562 cells. Differential DHS sites were enriched for key hematopoietic lineage transcription factor motifs, including SPI1 (PU.1), a known pioneer factor. We found PU.1 becomes up-regulated and increases binding at opened DHS sites by ChIP-seq with HDACi treatment, but show that increased PU.1 protein levels alone are sufficient for only modest increases in chromatin accessibility. PU.1 knockdown by shRNA failed to block the HDACi-induced chromatin accessibility and expression changes in K562, suggesting factors other than PU.1 are responsible for establishment of active enhancers in the HDACi induced differentiation process. SOURCE: Christopher,L,Frank (chris.frank@duke.edu) - Gregory Crawford Duke University