Genome-wide fetalization of enhancer architecture in heart disease [RNA-Seq]
Ontology highlight
ABSTRACT: Heart disease is associated with re-expression of key transcription factors normally active only during prenatal development of the heart. However, the impact of this reactivation on the genome-wide regulatory landscape in heart disease has remained obscure. Here we show that pervasive epigenomic changes occur in heart disease, with thousands of regulatory sequences reacquiring fetal-like chromatin signatures. We used RNA-seq and ChIP-seq targeting a histone modification associated with active transcriptional enhancers to generate genome-wide enhancer maps from left ventricle tissue from 18 healthy controls and 18 individuals with idiopathic dilated cardiomyopathy (DCM). Healthy individuals had a highly reproducible epigenomic landscape, consisting of more than 31,000 predicted heart enhancers. In contrast, we observed reproducible disease-associated gains or losses of activity at more than 7,500 predicted heart enhancers. Next, we profiled human fetal heart tissue by ChIP-seq and RNA-seq. Comparison with adult tissues revealed that the heart disease epigenome and transcriptome both shift toward a fetal-like state, with more than 3,400 individual enhancers sharing fetal regulatory properties. Our results demonstrate widespread epigenomic changes in DCM, and we provide a comprehensive data resource (http://heart.lbl.gov) for the mechanistic exploration of heart disease etiology.
Project description:Heart disease is associated with re-expression of key transcription factors normally active only during prenatal development of the heart. However, the impact of this reactivation on the genome-wide regulatory landscape in heart disease has remained obscure. Here we show that pervasive epigenomic changes occur in heart disease, with thousands of regulatory sequences reacquiring fetal-like chromatin signatures. We used RNA-seq and ChIP-seq targeting a histone modification associated with active transcriptional enhancers to generate genome-wide enhancer maps from left ventricle tissue from 18 healthy controls and 18 individuals with idiopathic dilated cardiomyopathy (DCM). Healthy individuals had a highly reproducible epigenomic landscape, consisting of more than 31,000 predicted heart enhancers. In contrast, we observed reproducible disease-associated gains or losses of activity at more than 7,500 predicted heart enhancers. Next, we profiled human fetal heart tissue by ChIP-seq and RNA-seq. Comparison with adult tissues revealed that the heart disease epigenome and transcriptome both shift toward a fetal-like state, with more than 3,400 individual enhancers sharing fetal regulatory properties. Our results demonstrate widespread epigenomic changes in DCM, and we provide a comprehensive data resource (http://heart.lbl.gov) for the mechanistic exploration of heart disease etiology.
Project description:Development and function of the human heart depend on the dynamic control of tissue-specific gene expression by distant-acting transcriptional enhancers. While large numbers of heart enhancers have been identified using the mouse as a model system, many of these regulatory sequences are poorly conserved in the human genome. To generate an accurate genome-wide map of human heart enhancers, we used an epigenomic enhancer discovery approach and identified ~6,200 candidate enhancer sequences directly from fetal and adult human heart tissue. Consistent with their predicted function, these elements were markedly enriched near genes implicated in heart development, function and disease. To further validate their in vivo enhancer activity, we tested 65 of these human sequences in a transgenic mouse enhancer assay and observed that 43 (66%) drove reproducible reporter gene expression in the heart. These results support the discovery of a genome-wide set of non-coding sequences highly enriched in human heart enhancers which is likely to facilitate down-stream studies of the role of enhancers in development and pathological conditions of the heart. Examination of AcCBP/p300 binding in human adult heart, human fetal (16wk) heart and mouse postnatal day 2 heart
Project description:Development and function of the human heart depend on the dynamic control of tissue-specific gene expression by distant-acting transcriptional enhancers. While large numbers of heart enhancers have been identified using the mouse as a model system, many of these regulatory sequences are poorly conserved in the human genome. To generate an accurate genome-wide map of human heart enhancers, we used an epigenomic enhancer discovery approach and identified ~6,200 candidate enhancer sequences directly from fetal and adult human heart tissue. Consistent with their predicted function, these elements were markedly enriched near genes implicated in heart development, function and disease. To further validate their in vivo enhancer activity, we tested 65 of these human sequences in a transgenic mouse enhancer assay and observed that 43 (66%) drove reproducible reporter gene expression in the heart. These results support the discovery of a genome-wide set of non-coding sequences highly enriched in human heart enhancers which is likely to facilitate down-stream studies of the role of enhancers in development and pathological conditions of the heart.
Project description:It is hypothesized that the postnatal heart adopts a fetal-like transcriptional state in response to cardiac stress. Here, we analyse the transcriptome of 74,451 nuclei from fetal, non-diseased and early-onset DCM samples, which revealed 7 broad cell clusters across fetal, ND and DCM samples. We find that there are no statistically significant shifts in cellular composition between DCM and ND hearts. Also, pseudo-bulk profiling revealed that transcriptional pathways perturbed in DCM are predominantly associated with cardiomyocytes, fibroblasts and immune cells. We advance the hypothesis that only a small subset (<10%) of fetal genes is re-engaged in both cardiomyocyte and cardiac fibroblast of DCM. This study provides a framework to identify critical gene expression networks that underpin disease pathogenesis independent of genetic aetiology.
Project description:We conducted chromatin immunoprecipitation followed by sequencing (ChIP-seq) and proximity ligation-assisted ChIP-seq (PLAC-seq) for enhancers and promoters (E-P) using left ventricular tissues from dilated cardiomyopathy (DCM) patients and non-heart failure (NF) donors. Differential active enhancer H3K27ac and promoter H3K4me3 regions were identified between NF and DCM. While the average read density (ARD) for H3K27ac is similar between NF and DCM, the ARD of H3K4me3 is significantly lower in DCM samples than in NF.Super-enhancer (SE) analysis revealed that 929 and 129 genes linked to NF- and DCM-specific SE, respectively, and three unique SE-associated genes between NF and DCM were identified.Moreover, the differential E-P interactions were observed in the known heart failure gene loci and are correlated with the gene expression levels. Motif analysis identified known cardiac factors and possible novel players for DCM. We have established cistrome of four histone modifications and long-range chromatin interaction for enhancers and promoters in NF and DCM tissues. The differential histone modifications and E-P interactions were found in DCM, and these differences were associated with the gene expression level of a subset of disease-associated genes in human heart failure.
Project description:We conducted chromatin immunoprecipitation followed by sequencing (ChIP-seq) and proximity ligation-assisted ChIP-seq (PLAC-seq) for enhancers and promoters (E-P) using left ventricular tissues from dilated cardiomyopathy (DCM) patients and non-heart failure (NF) donors. Differential active enhancer H3K27ac and promoter H3K4me3 regions were identified between NF and DCM. While the average read density (ARD) for H3K27ac is similar between NF and DCM, the ARD of H3K4me3 is significantly lower in DCM samples than in NF.Super-enhancer (SE) analysis revealed that 929 and 129 genes linked to NF- and DCM-specific SE, respectively, and three unique SE-associated genes between NF and DCM were identified.Moreover, the differential E-P interactions were observed in the known heart failure gene loci and are correlated with the gene expression levels. Motif analysis identified known cardiac factors and possible novel players for DCM. We have established cistrome of four histone modifications and long-range chromatin interaction for enhancers and promoters in NF and DCM tissues. The differential histone modifications and E-P interactions were found in DCM, and these differences were associated with the gene expression level of a subset of disease-associated genes in human heart failure.
Project description:This study attempts at investigating the changes in cardiac gene expression that occur in Dilated Cardiomyopathy (DCM). DCM in Dobermans and Boxers are the focus of this study. Control heart tissue as well as Pacing tissue used is from mongrel dogs. Keywords: control vs pacing vs disease; strain specific disease 3 Dobermans-DCM, 4 Boxers-DCM, 3 mongrels-control and 3 mongrels-pacing
Project description:The cTnT-DK210 DCM mice showed ABRA protein deficiency, sarcomeric disruption, and compromised heart contractility. Heart-specific expression of ABRA in cTnT-DK210 mice restored sarcomeric structures, reversed the disease progress, and rescued the DCM phenotypes. ABRA deficiency and compromised downstream serum response factor-regulated muscle gene expression play a key role in familial DCM caused by the cTnT-DK210 mutation. ABRA is a good therapeutic gene for cTnT-DK210-induced DCM and could be translated to other cTnT mutations-induced familial DCM.
Project description:The mammalian telencephalon plays critical roles in cognition, motor function, and emotion. While many of the genes required for its development have been identified, the distant‐acting regulatory sequences orchestrating their in vivo expression are mostly unknown. Here we describe a digital atlas of in vivo enhancers active in subregions of the developing telencephalon. We identified over 4,600 candidate embryonic forebrain enhancers and studied the in vivo activity of 329 of these sequences in transgenic mouse embryos. We generated serial sets of histological brain sections for 145 reproducible forebrain enhancers, resulting in a publicly accessible web‐based enhancer atlas comprising over 33,000 sections. We show how this large collection of annotated telencephalon enhancers can be used to study the regulatory architecture of individual genes, to examine the sequence motif content of enhancers, and to drive targeted reporter or effector protein expression in experimental applications. Furthermore, we used epigenomic analysis of human and mouse cortex tissue to directly compare the genome‐wide enhancer architecture in these species. This atlas provides a primary resource for investigating gene regulatory mechanisms of telencephalon development and enables studies of the role of distant‐acting enhancers in neurodevelopmental disorders. Examination of p300 binding in mouse embryonic stage 11.5 forebrain, mouse postnatal (P0) cortex tissue and human fetal (gestational week 20) cortex
Project description:About one third of dilated cardiomyopathy (DCM) cases are caused by mutations in sarcomere or cytoskeletal proteins. Yet treating the cytoskeleton directly is not possible because drugs that bind to actin are not well tolerated. Mutations in the actin binding protein CAP2 can cause DCM and knockout mice, either whole body (CAP2 KO) or cardiomyocyte specific knockouts (CAP2 CKO), develop DCM with cardiac conduction disease. RNA-seq analysis of CAP2 KO hearts and isolated cardiomyocytes revealed over-activation of fetal genes including serum response factor (SRF) regulated genes such as Myl9 and Acta2 prior to the emergence of cardiac disease. To test if we could treat CAP2 KO mice, we synthesized and tested the SRF inhibitor CCG-1423-8u. CCG-1423-8u reduced expression of the SRF targets Myl9 and Acta2, as well as the biomarker of heart failure, NPPA. The median survival of CAP2 CKO mice was 98 days, while CCG-1423-8u treated CKO mice survived for 116 days and also maintain normal cardiac function longer. These results suggest that some forms of sudden cardiac death and cardiac conduction disease are under cytoskeletal stress and that inhibiting signaling through SRF may benefit DCM by reducing cytoskeletal stress.