ETV2/ER71 regulates hematovascular lineage generation and vascularization through an H3K9 demethylase, KDM4A

ETV2/ER71, an ETS transcription factor, is critical for hematopoiesis and vascular development. However, knowledge on the molecular mechanisms behind ETV2-mediated gene transcription is limited. Here, we show that ETV2 together with KDM4A, an H3K9 demethylase, regulates hematopoietic and endothelial genes. Etv2-/- mouse embryonic stem cells (mESCs), which fail to generate hematopoietic and endothelial cells, showed enhanced levels of H3K9me3 on hematopoietic and endothelial genes. ETV2 interacts with KDM4A and the ETV2-mediated transcriptional activation of hematopoietic and endothelial genes is dependent on KDM4A histone demethylase activity. ETV2 and KDM4A co-occupy the transcription regulatory regions of genes whose expression is directly regulated by ETV2. Mice lacking Kdm4a and Etv2 in endothelial cells (Cdh5Cre;Kdm4af/f;Etv2f/f) displayed a more severe defect in perfusion recovery and neovascularization compared with Cdh5Cre;Kdm4af/f, Cdh5Cre;Etv2f/f mice and controls. Collectively, we demonstrated that ETV2 interacts with KDM4A and that this interaction is critical for FLK1+ cell generation, differentiation into the downstream lineages, and vascular regeneration.