Genome-wide binding profiles of JUNB in unstimulated HoxER-PU.1 WT and PU.1 KO neutrophils

Neutrophils are essential first line defense cells against invading pathogens, yet their inappropriate activation contributes to immunological diseases and can cause collateral tissue damage. However, neutrophil-intrinsic mechanisms adjusting an appropriate inflammatory response are unknown. Herein, we conditionally deleted PU.1, a key myeloid transcription factor, from the neutrophils of mice undergoing fungal infection, and then performed comprehensive epigenomic profiling. We find that a major function of PU.1 is to restrain the neutrophils’ immune response by broadly suppressing genomic enhancer outputs via recruiting histone deacetylase activity, thereby limiting the immune-stimulatory AP1-transcription factor JUNB from entering chromatin. Thus, PU.1 acts as rheostat of the inflammatory chromatin state, safeguarding the neutrophil epigenome from undergoing uncontrolled activation prior to pathogenic stimulation. Examination of JUNB occupany in unstimulated HoxER-PU.1 WT and PU.1 KO neutrophils by deep sequencing in duplicates.