Hi-C2 of mouse splenic macrophages and pDCs

The transcriptional repressor Zeb2 regulates development of many cell fates among somatic, neural and hematopoietic lineages, but the basis for its requirement in these diverse linages is unclear. Our recent study uncovered a mutually repressive regulatory circuit between Id2 and Zeb2, and predicted that Zeb2 should be positively regulated by members of the E protein family of transcription factors. Here, we identified a 400bp enhancer region located 165 kilobases (kb) upstream of the Zeb2 transcriptional start site (TSS) that binds the E proteins E2A and E2-2 at several E-box motifs and is active in hematopoietic lineages. Germline deletion of this 400bp region (Zeb2 –165–/– mice) specifically prevented Zeb2 expression in hematopoietic stem cell (HSC) derived lineages. Zeb2 –165–/– mice lacked development of pDCs, monocytes, and B cells. Surprisingly, all macrophages in Zeb2 –165–/– mice were exclusively of embryonic origin. Using single-cell chromatin profiling, we identified a second Zeb2 enhancer located at +164kb that is selectively active in embryonically derived lineages, but not in lineages derived from HSCs. Thus, Zeb2 expression in adult, but not embryonic, hematopoiesis is selectively controlled by the –165kb Zeb2 enhancer. Overall design: Hi-C2 on: splenic macrophages (2 biological replicates) and pDCs (3 biological replicates) sorted from WT B6 mice; splenic macrophages (2 biological replicates) sorted from Zeb2-165-/- B6 mice