scATAC-seq reveals epigenetic changes associated with decreased myelomonocytic priming in gata2b mutants. (A) Uniform manifold approximation and projection (UMAP) of marrow cells in WT (n = 2), gata2b^het (n = 2), and gata2b^ko (n = 3). 10× Genomics scATAC-seq data are shown. BcellProg/Prec, B-cell progenitors and precursors; VE, vascular endothelium. (B) Quantification of hematopoietic cell types from scATAC-seq in WT and gata2b^ko zebrafish. *P < .05, Fisher’s exact test. (C) Differential TF motif score analysis between WT and gata2b^ko (KO) samples within HSPC-MPP population. (D) Feature plots of WT and gata2b^ko samples for NFIC motif score within individual cells in the HSPC-MPP population. (E) Violin plot of NFIC TF motif score in WT and gata2b^ko HSPC-MPPs. *P = .0014, 2-tailed Student t test. (F) Differential TF motif score analysis between WT and gata2b^ko (KO) samples within myeloid progenitors. (G) Feature plots of WT and gata2b^ko samples for SPI1 motif score within individual cells in the myeloid progenitor and granulocyte populations. (H) Violin plot of SPI1 TF motif score in WT and gata2b^ko myeloid progenitors. *P = 1.31 × 10⁻¹², 2-tailed Student t test.