show Abstracthide AbstractThe role of the lineage-determining transcription factor, Interferon regulatory factor (IRF8), in microglia remains unelucidated. We report the genome-wide chromatin status in adult wild-type (WT) and IRF8-knockout (IRF8KO) microglia by ATAC-Seq. Deep-sequencing and subsequent differential analysis revealed that chromatin accessibility in microglia requires IRF8. At the same time, the loss of IRF8 gains aberrant chromatin accessibility that potentially confers mRNA transcription of the genes upregulated in IRF8KO microglia. This study provides a novel insight into understanding epigenetic regulation in microglia. Overall design: Examination of chromatin accessibility in microglia.