Loss of ARID1B perturbs expression and chromatin accessibility in murine hematopoietic stem and progenitor cells. (A) Expression levels of key genes involved in hematopoiesis (Csf1r, Csf1, Cd34, Flt3, and Il1r1) in WT and Arid1b KO GMPs. (B) ATAC-seq peaks identified in WT and Arid1b^−/− Lin⁻Kit⁺ BM cells. Peaks that are enriched significantly (false discovery rate of <0.01) in either genotype are depicted in red. (C) Heat map shows ATAC-seq peaks (±1 kilo base) identified using DiffBind as significantly closed in ARID1B-deficient cells. (D) Box plots show normalized read counts in the open chromatin regions enriched in either WT or KO cells. The width of the box plots is an indicator of the number of enriched sites for each group. Statistical significance was calculated using Wilcoxon rank-sum test. (E) Distribution of ATAC-seq peaks either lost or gained in Arid1b KO Lin⁻Kit⁺ BM cells. (F) Top 5 Homer de novo motifs enriched in genomic loci with significantly reduced ATAC-seq signal in Arid1b KO cells. A hypergeometric test was used to calculate the statistical significance of the enrichment of the identified motif in the input sequences compared with a background model. TTS; transcriptional termination site; UTR, untranslated region.