The Reg1/Reg3-Nfkbiz axis regulates lineage priming of HSCs/early MPPs via chromatin remodeling. (A) Schematic representation of scATAC-seq using Flt3^–CD48^– LSK. In each genotype, samples are pooled from multiple mice to create a single sample for sequencing, as indicated by the number of mice represented. (B) UMAP visualization of all cells obtained from scATAC-seq data. Colors represent the cluster identity. (C) Heatmap showing chromatin accessibility for stemness-related and lineage-associated genes. (D) Cluster distribution of single cells across the indicated genotypes. Colors represent the cluster identity as in (B). (E) A 2-dimensional projection of 13859, 10991, 9936, and 6902 single cells from control, DKO^CreERT2, Nfkbiz^CreERT2, and TKO^CreERT2, respectively, onto the UMAP plot (B). (F) Heatmap showing differential chromatin accessibilities of the selected myeloid-related gene loci between control and DKO^CreERT2 cells in C1 to C5. (G-H) Volcano plot showing the comparison of TF motif enrichment between control vs DKO^CreERT2 in C1 to C5 (G) and C6 to C8 (H).