GSE185682
Bulk RNA-seq analysis of Etv2 induced EB differentiation.
The vasculature is an essential organ for the delivery of blood and oxygen to all tissues of the body and thus relevant to the treatment of ischemic diseases, injury-induced regeneration, and solid tumor growth. Therefore, the definition of pioneer factors and regulatory pathways that govern the specification and differentiation of endothelial progenitors will serve as a platform for targeted therapies to promote cardiovascular regeneration and treatment of solid organ tumors. Previously, we demonstrated that ETV2 was an essential transcription factor for the development of cardiac, endothelial and hematopoietic lineages.  Here, we report that ETV2 functions as a novel pioneer factor that relaxes closed chromatin and regulates endothelial development. By comparing engineered embryonic stem cell differentiation and reprogramming models with single cell RNA-seq, ATAC-seq and ChIP-seq techniques, we demonstrated that ETV2 was able to bind nucleosomal DNA and function as a pioneer factor independent of the cellular context. We determined that ETV2 executes a pioneering role by recruiting BRG1 to remodel chromatin around endothelial genes and help maintain an open configuration.  ETV2 chromatin binding also resulted in increased H3K27ac deposition.  Collectively, these results will serve as a platform for the development of therapeutic initiatives directed towards cardiovascular and oncological diseases. Overall design: Total RNA was isolated from iHA-Etv2 MEFs and EBs using the RNeasy kit (Qiagen, Cat# 74104) according to the manufacturer's protocol. Briefly, cells were lysed in RLT-lysis buffer, followed by a column-based purification process and on-column DNA digestion. Complementary DNA (cDNA) was synthesized using the SuperScript IV VILO kit (Thermo Fisher Scientific, Cat# 11756050) according to the manufacturer's protocol. Quantitative polymerase chain reaction (qPCR) was performed with ABI Taqman probe sets. Taqman probes used in this study include VIC-labeled GAPDH:4352339E, FAM-labeled Etv2: mm01176581_g1, Flk1: mm00440099_m1, PECAM (Cd31): mm0124616 7_m1, Tie2: mm01256892_ m1, Cdh5: mm00486938_m1, Lmo2: Mm00493153_m1, Sox18: Mm00656049_gH, Smarca4 (Brg1): Mm01151944_m1, Emcn: Mm00497495_m1, Mmp9: Mm00442991_m1, Hopx: Mm00558630_m1, Otor: Mm00498571_m1, Lax1: Mm00556050_m1, Chd8: Mm01316316_m1, Dek: Mm01351566_m1 and Znhit: Mm01201686_m1