Enrichment of anemia-activated genes at loci containing E-box–GATA composite element sequences. (A) Experimental strategy for scRNA-seq of erythroid precursors from control and PHZ-induced anemic spleens. (B) UMAP representation of control (7118 cells) and PHZ-treated (10 305 cells) samples. Annotation indicates 18 distinct color-coded clusters. (C) Percentages of HSPCs and erythroid clusters relative to total cells analyzed in control and anemia samples. Cells not annotated as HSPC or erythroid are shown as “others.” Statistical significance between cell percentages in control and anemia determined using a Fisher exact test. (D) Dot plot depicting changes in normalized average expression (color of dot) and expression in a percentage of cells (size of dot) of hematopoietic and erythropoietic genes in HSPCs and erythroid cells. (E) Bar graph of Samd14 transcript levels in CD71⁺ cells from control and anemia samples (normalized expression of Tfrc > 0). Statistical significance calculated using Wilcoxon test. (F) The percentage of Samd14 expressing cells (depicted in a line graph) in control and anemia CD71⁺ cells. Statistical significance was determined using Fisher exact test. (G) Bar graph comparison of SLC15A37 and SOX6 expression in erythroid precursors from healthy controls and patients with aplastic anemia, alongside control and anemia data from PHZ-treated mouse samples. Statistical significance determined using unpaired Student t test. (H) In each cluster, ratio indicates the proportion of RNA transcripts annotated within 100 kb of CANNTG[N6-14]AGATAA (EGA) within all detected RNA transcripts (orange bars) or anemia-upregulated RNA transcripts (black bars; fold >1.5; adjusted P < .05). (I) In each cluster, ratio indicates the proportion of detected RNA transcripts within 100 kb of GATA/TAL-occupied EGA sequences (GSE51338) or GATA2 (GSE29193) and TAL1 (GSE36029) within all detected RNA transcripts (blue bars) or anemia-upregulated RNA transcripts (gray bars). Statistical significance was determined using Wilcoxon test (∗P < .05; ∗∗P < .01; ∗∗∗P < .001; ∗∗∗∗P < .0001). RBC, red blood cell; UMAP, uniform manifold approximation and projection.