Etv6 binding precedes cohesin binding at cis-regulatory elements of genes upregulated during erythropoiesis. (A) Schematic of methodology to identify cohesin complex interacting proteins at chromatin. (B) Volcano plot showing differences in pull down of Stag2 between Luc1_HPC (4 experimental replicates) and shS2_1_HPC (4 experimental replicates). The brown colored dots show significantly associated proteins (padj < 0.1, log2FC 0.33). (C) Upper: Venn diagram displaying validation of significant Stag2-associated proteins from panel B after RIME pull down with Rad21 (4 technical replicates, Luc1_HPC). Lower right: putative cohesin-interacting proteins that bind together at chromatin; lower left: top 5 enrichments of gene ontology (GO) molecular functions of the final full list of cohesin interactors (scale is −log10 [q value]). (D) Average profiles demonstrating the enrichment of the specified prebound hTF at the erythroid differentiation tiers in unstimulated HPC. (E) Coimmunoprecipitation experiments confirm interaction of Etv6 with Stag2 and Rad21.