GSE138106
The histone methyltransferase Setd8 alters the chromatin landscape and regulates the expression of key transcription factorsduring erythroid differentiation
SETD8 is the sole methyltransferase capable of mono-methylating histone H4, lysine 20. SETD8 is highly expressed in erythroid cells and erythroid deletion of Setd8 is embryonic lethal by embryonic day 11.5 (E11.5) due to profound anemia, suggesting it has an erythroid-specific function. To gain insights into the function of SETD8 during erythroid differentiation, we performed ATAC-seq on sorted populations of E10.5 Setd8 null and control erythroblasts. Accessibility profiles were integrated with  expression changes and a mark of heterochromatin (H3K27me3) performed in wild type E10.5 erythroblasts to further understand the role of SETD8 in erythropoiesis.  Data integration identified regions of greater chromatin accessibility in Setd8 null cells that co-located with H3K27me3 in wild type E10.5 erythroblasts suggesting that these regions, and their associated genes, are repressed during normal erythropoiesis.  Pathway analysis of genes identified through data integration revealed stemness-related pathways. Among those genes were multiple transcriptional regulators active in multipotent progenitors but repressed during erythroid differentiation including Hhex, Hlx,  and Gata2. Consistent with a role for SETD8 in erythroid specification, SETD8 expression is upregulated upon erythroid commitment, and Setd8 disruption impairs erythroid colony forming ability. Taken together, our results suggest that Setd8 is important for the establishment of appropriate patterns of gene expression during erythroid differentiation. Overall design: Biological replicates were generated for setd8-null(2) and setd8-control(3) embryos. Biological replicates were aggregated, sequencing depth normalized, and a continuous log2 ratio was computed to identify regions of differential accessiblity in the setd8-null compared to control.