Anemia increased regulon activity of EGA TFs. (A) Heatmap of scaled regulon activity scores based on the coexpression of predicted target genes and TF recognition motif enrichment, in HSPC and erythroid clusters. Inset: heatmap of GATA2 regulon activity and a cluster of regulons (including GATA1) with high activity in E3 cells. (B) Violin plot of GATA2, GATA1, and TAL1 regulon activity scores in every cell of HSPCs and erythroid clusters. Red, control; and blue, PHZ. Statistics were calculated using Wilcoxon test. (C) Bar graph depicting percentage of shared regulon activity between individual TFs (ranked per the order of shared activity) with the GATA1/TAL1 coregulons. All TFs with triregulon overlap of more than 10% are shown (inset). Complete list of TFs are given in supplemental Table 4. (D) UMAP representation of HSPC and erythroid cells from control and anemia samples that are color-coded based on pseudotime projections from Monocle3. (E) Volcano plot of all EGA GATA/TAL1-occupied genes in E3. Significantly upregulated genes were selected based on fold change >1.5 and adjusted P < .05. Red dots indicate Ssx2ip, Samd14, and Ttll12. (F) Enrichr analysis of 65 anemia upregulated genes associated with S14E-like enhancers, using data from the OMIM and GWAS catalog. (G) Bar graph quantitation of Ssx2ip expression level in sorted populations of hematopoietic cells isolated from mouse bone marrow, as described by Lara-Astiaso et al.²¹ Statistical significance was determined using two-tailed unpaired Student t test. ∗P < .05; ∗∗∗P < .001; ∗∗∗∗P < .0001. CLP, common lymphoid progenitor; CMP, common myeloid progenitor; EryA, Ter119⁺CD71⁺FSC^high; EryB, Ter119⁺CD71⁺FSC^low; HSC, hematopoietic stem cells; GMP, granulocyte monocyte progenitor; LT-HSC, long-term hematopoietic stem cells; MEP, megakaryocyte erythroid progenitor; MF, macrophage; MPP, multipotent progenitors; NK, natural killer cells; OMIM, Online Mendelian Inheritance in Man.