Regulation of angiotensin II actions by enhancers and super-enhancers in vascular smooth muscle cells

Sadhan Das,Selena Zhang,Rama Natarajan,Marpadga A Reddy,Zhuo Chen,Ye Jia,Rituparna Ganguly,Parijat Senapati,Anita Bansal,Linda Lanting,Varun Mandi,Dustin E Schones,Amy Leung,Xiwei Wu

doi:10.1038/s41467-017-01629-7

Sadhan Das, Selena Zhang + Show 12 more

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https://doi.org/10.1038/s41467-017-01629-7

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Journal: Nature Communications	Publication Date: Nov 13, 2017
Citations: 76	License type: open-access

Affiliation: City of Hope, Beckman Research Institute

Abstract

Angiotensin II (AngII) promotes hypertension and atherosclerosis by activating growth-promoting and pro-inflammatory gene expression in vascular smooth muscle cells (VSMCs). Enhancers and super-enhancers (SEs) play critical roles in driving disease-associated gene expression. However, enhancers/SEs mediating VSMC dysfunction remain uncharacterized. Here, we show that AngII alters vascular enhancer and SE repertoires in cultured VSMCs in vitro, ex vivo, and in AngII-infused mice aortas in vivo. AngII-induced enhancers/SEs are enriched in binding sites for signal-dependent transcription factors and dependent on key signaling kinases. Moreover, CRISPR-Cas9-mediated deletion of candidate enhancers/SEs, targeting SEs with the bromodomain and extra-terminal domain inhibitor JQ1, or knockdown of overlapping long noncoding RNAs (lncRNAs) blocks AngII-induced genes associated with growth-factor signaling and atherosclerosis. Furthermore, JQ1 ameliorates AngII-induced hypertension, medial hypertrophy and inflammation in vivo in mice. These results demonstrate AngII-induced signals integrate enhancers/SEs and lncRNAs to increase expression of genes involved in VSMC dysfunction, and could uncover novel therapies.

Highlights

Angiotensin II (AngII) promotes hypertension and atherosclerosis by activating growthpromoting and pro-inflammatory gene expression in vascular smooth muscle cells (VSMCs)
In order to characterize the AngII-regulated enhancers that might be involved in AngII-mediated gene expression in rat VSMCs (RVSMCs), we performed genome-wide chromatin immunoprecipitation (ChIP)-seq analysis using antibodies recognizing H3K4me[1] for candidate enhancers and H3K27ac for active enhancers[18] (Fig. 1a)
We examined two representative AngII-upregulated genes, namely, endothelial cell-specific molecule[1] (Esm1) and Sprouty Homolog[2] (Spry2), that are involved in VSMC growth, proliferation and inflammation[32,33], and one AngIIdownregulated gene, AngII Receptor Type1a (Agtr1a), which mediates AngII signaling involved in hypertension and CVD34

Summary

Introduction

Angiotensin II (AngII) promotes hypertension and atherosclerosis by activating growthpromoting and pro-inflammatory gene expression in vascular smooth muscle cells (VSMCs). JQ1 ameliorates AngII-induced hypertension, medial hypertrophy and inflammation in vivo in mice These results demonstrate AngII-induced signals integrate enhancers/SEs and lncRNAs to increase expression of genes involved in VSMC dysfunction, and could uncover novel therapies. Activation of aortic vascular smooth muscle cells (VSMCs) by the pro-inflammatory and pro-atherogenic growth factor (GF) angiotensin II (AngII) is a key event in the development of cardiovascular diseases (CVDs), such as hypertension and atherosclerosis[1,2]. AngII regulates gene expression via activation of transcription factors (TFs) such as AP1, NF-κB, and ETS1, and co-operating epigenetic mechanisms that include increased histone H3 lysine 9/14 acetylation (H3K9/14ac) as well as other histone modifications at target gene promoters[8,11]. The results reveal novel functional roles of enhancers/SEs in epigenetic mechanisms of AngII actions, which in turn could yield valuable new information for therapeutic intervention in CVDs

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