RNF20-mediated transcriptional pausing and alternative splicing of pro-angiogenic genes orchestrate vessel growth [04Po2t_OE_ERG_ChIP_HUV]

Signal-responsive gene expression is essential for vascular growth and patterning, yet the mechanisms allowing the integration of signaling inputs and transcriptional activities are largely unknown. Here we show that RNF20, the major E3 ubiquitin ligase of histone H2B, plays a key role during sprouting angiogenesis by mediating Pol II promoter-proximal pausing at pro-angiogenic genes. Furthermore, it orchestrates large-scale mRNA processing events, which change the bioavailability and function of critical pro-angiogenic factors, such as VEGFA. Mechanistically, we show that RNF20 restricts ERG-dependent gene activation through the VEGF-ERK1/2 axis while enabling Notch1 to bind to chromatin, thereby modulating the VEGF-Notch signaling circuits. Since perturbations of RNF20 are associated with cardiovascular malformations in human patients, our work may provide novel therapeutic avenues for diseases caused by vascular dysfunction. Overall design: HUVEC cells were transfected with lentivirus either with Ctr or ERG Over expression or STAT3 Over Expression. Chromatin was harvested to perform ChIP-seq.