ABSTRACT: Combined ablation of all 3 cardiac-expressed GRKs in the developing mouse heart impaired Hedgehog/Smoothened and GATA signaling, recapitulating heart abnormalities of human Complete Atrioventricular Septal Defect.
Project description:Molecular Signatures of cardiac defects in Down syndrome lymphoblastoid cell lines. In this study, we want to identify genes and pathways specifically dysregulated in atrioventricular septal defect and /or atrial septal defect + ventricular septal defect in case of trisomy 21. Total RNA obtained from DS lymphoblastoid cell lines without congenital heart disease compared to cell lines from DS with congenital heart disease.
Project description:Molecular Signatures of cardiac defects in Down syndrome lymphoblastoid cell lines. In this study, we want to identify genes and pathways specifically dysregulated in atrioventricular septal defect and /or atrial septal defect + ventricular septal defect in case of trisomy 21.
Project description:Malformations of the cardiovascular system are the most common type of birth defect in humans, affecting predominantly the formation of valves and septa. During heart valve and septa formation, cells from the atrio-ventricular canal (AVC) and outflow tract (OFT) regions of the heart undergo an epithelial-to-mesenchymal transformation (EMT) and invade the underlying extracellular matrix to give rise to endocardial cushions. Subsequent maturation of newly formed mesenchyme cells leads to thin stress-resistant leaflets. TWIST1 is a basic helix-loop-helix transcription factor expressed in newly formed mesenchyme cells of the AVC and OFT that has been shown to play roles in cell survival, cell proliferation and differentiation. However, the role and downstream targets of TWIST1 during heart valve formation remain unclear. To identify genes important for heart valve development downstream of Twist1 we performed global gene expression profiling of AVC, OFT, atria and ventricles of the embryonic day 10.5 mouse heart by tag-sequencing (Tag-seq). Using this resource we identified a novel set of 1246 genes, including 201 regulators of transcription, enriched in the valve forming regions of the heart. We compared these genes to a Tag-seq library from the Twist1 null developing valves revealing significant gene expression changes. These changes were consistent with a role of TWIST1 in controlling differentiation of mesenchymal cells following their transformation from endothelium in the mouse. To study the role of TWIST1 at the DNA level we performed chromatin immunoprecipitation and identified novel direct targets of TWIST1 in the developing heart valves. Our findings are consistent with a role for TWIST1 in the differentiation of AVC mesenchyme post-EMT in the mouse, and suggest that TWIST1 exerts its function by direct DNA binding to activate valve specific gene expression. Profiled the AVC, OFT, atria and ventricles of the embryonic day 10.5 mouse heart by tag-sequencing (Tag-seq) (no replicates). We also produced a Tag-seq library from Twist1 null developing valves to reveal the gene expression changes associated with loss of this gene.
Project description:To understand the function of Wnt/β-catenin signaling-activated cardiomyocytes (β-cat ON CMs), we performed RNA-Seq on β-cat ON and OFF CMs at the atrioventricular canal (AVC) in the heart, respectively. Our analyses indicated that β-cat ON CMs upregulate genes related to blood vessel development.
Project description:Malformations of the cardiovascular system are the most common type of birth defect in humans, affecting predominantly the formation of valves and septa. During heart valve and septa formation, cells from the atrio-ventricular canal (AVC) and outflow tract (OFT) regions of the heart undergo an epithelial-to-mesenchymal transformation (EMT) and invade the underlying extracellular matrix to give rise to endocardial cushions. Subsequent maturation of newly formed mesenchyme cells leads to thin stress-resistant leaflets. TWIST1 is a basic helix-loop-helix transcription factor expressed in newly formed mesenchyme cells of the AVC and OFT that has been shown to play roles in cell survival, cell proliferation and differentiation. However, the role and downstream targets of TWIST1 during heart valve formation remain unclear. To identify genes important for heart valve development downstream of Twist1 we performed global gene expression profiling of AVC, OFT, atria and ventricles of the embryonic day 10.5 mouse heart by tag-sequencing (Tag-seq). Using this resource we identified a novel set of 1246 genes, including 201 regulators of transcription, enriched in the valve forming regions of the heart. We compared these genes to a Tag-seq library from the Twist1 null developing valves revealing significant gene expression changes. These changes were consistent with a role of TWIST1 in controlling differentiation of mesenchymal cells following their transformation from endothelium in the mouse. To study the role of TWIST1 at the DNA level we performed chromatin immunoprecipitation and identified novel direct targets of TWIST1 in the developing heart valves. Our findings are consistent with a role for TWIST1 in the differentiation of AVC mesenchyme post-EMT in the mouse, and suggest that TWIST1 exerts its function by direct DNA binding to activate valve specific gene expression.
Project description:Goals of this study were to identify new candidates involved in the development of the Atrioventricular cushions in the mouse heart. Keywords = Heart development Keywords = Atrioventricular cushions Keywords = Atrioventricular junction Keywords = Atrioventricular myocardium Keywords = embryonic day ED10.5-11.0 Keywords = ventricles Keywords: development analysis
Project description:Hypereosinophilic syndrome is a progressive disease with extensive eosinophilia that results in organ damage. Patients suffer from frequent cardiac pathologies and a high mortality rate. A better understanding of the mechanisms of eosinophil-mediated tissue damage would benefit the development of new therapies. Here, we describe the cardiac pathologies that develop in a mouse model of hypereosinophilic syndrome. These IL-5 transgenic mice exhibited decreased left ventricular function already at a young age. Cardiac function worsened with age and heart weight increased. Moreover, hypereosinophilic mice developed different pathologies of the cardiac conductive system, including 2nd degree atrioventricular block and atrioventricular reentry. Cardiomyocytes from IL-5 transgenic mice showed reduced contractility. Despite immune infiltrates in the lungs, doppler echocardiography revealed no signs of pulmonary hypertension in these mice. Mechanistically, we demonstrated eosinophil infiltration of the heart tissue that lead to an inflammatory environment. Eosinophils were 100-fold more abundant in the hearts of hypereosinophilic mice than controls. Gene expression signatures showed tissue damage as well as repair and remodeling processes. Our results suggest that hypereosinophilia leads to infiltration of the heart tissue by eosinophils and tissue damage. The ongoing remodeling and repair processes are insufficient or maladapted to maintain heart function resulting in progressive deterioration.
Project description:MicroRNAs (miRNAs) regulate transcription factors and relate to ventricular septal defect (VSD) occurrence, progression and outcome. Recently, circulating miRNAs from maternal blood and amniotic fluid have been used as biomarkers for congenital heart defect (CHD) diagnosis. However, whether circulating miRNAs are associated with foetal heart tissue remains unknown. Dimethadione (DMO) induced a VSD rat model and the miRNA expression profiles of the myocardium, amniotic fluid and maternal serum were analysed. MiRNAs were differentially expressed in the myocardium, amniotic fluid or maternal serum of VSD foetal rats and might be involved in cardiomyocyte differentiation and apoptosis.
Project description:This project aims to study exomes from families and trios with
congenital heart disease (CHD). The samples have been collected under
the Competence Network - Congenital Heart Defects in Berlin, Germany.
The phenotypes are mainly left ventricular outflow obstruction (aortic
stenosis, bicuspd aortic valve disease coarctation and hypoplastic
left heart), but will also include samples with hypoplastic right
heart and atrioventricular septal defects. We will perform whole exome
sequencing using Agilent sequence capture and Illumina HiSeq
sequencing.
Project description:This project aims to study exomes from families and trios with
congenital heart disease (CHD). The samples have been collected under
the Competence Network - Congenital Heart Defects in Berlin, Germany.
The phenotypes are mainly left ventricular outflow obstruction (aortic
stenosis, bicuspd aortic valve disease coarctation and hypoplastic
left heart), but will also include samples with hypoplastic right
heart and atrioventricular septal defects. We will perform whole exome
sequencing using Agilent sequence capture and Illumina HiSeq
sequencing.