Similar Datasets
Project description:Understanding how the atrial and ventricular chambers of the heart maintain their distinct identity is a prerequisite for treating chamber-specific diseases. Here, we selectively inactivated the transcription factor Tbx5 in the atrial working myocardium of the neonatal mouse heart to show that it is required to maintain atrial identity. Atrial Tbx5 inactivation downregulated highly chamber specific genes such as Myl7 and Nppa, and increased expression of ventricular identity genes including Myl2. Using combined single nucleus transcriptome and open chromatin profiling, we assessed genomic accessibility changes underlying the altered atrial identity expression program, identifying 1846 genomic loci with greater accessibility in control atrial cardiomyocytes compared to KO aCMs. 69% of the control-enriched ATAC regions were bound by TBX5, demonstrating a role for TBX5 in maintaining genomic accessibility. These regions were associated with genes that had higher expression in control aCMs compared to KO aCMs, suggesting they act as TBX5-dependent enhancers. To confirm this hypothesis we analyzed chromatin looping of enhancers marked by H3K27Ac using HiChIP and found 510 chromatin loops that were sensitive to TBX5 dosage. Of the loops enriched in control aCMs, 73.7% contained anchors in control-enriched ATAC regions. Conversely, Tbx5 overexpression in the ventricular myocardium drove atrial gene expression. Together, these data demonstrate a role for TBX5 in maintaining the atrial gene expression program by binding to atrial enhancers to preserve tissue-specific chromatin architecture. We highlight this phenomenon at major atrial identity genes including Nppa, Bmp10 and Myl7.
2023-08-11 | GSE222373 | GEO
Project description:Understanding how the atrial and ventricular chambers of the heart maintain their distinct identity is a prerequisite for treating chamber-specific diseases. Here, we selectively inactivated the transcription factor Tbx5 in the atrial working myocardium of the neonatal mouse heart to show that it is required to maintain atrial identity. Atrial Tbx5 inactivation downregulated highly chamber specific genes such as Myl7 and Nppa, and increased expression of ventricular identity genes including Myl2. Using combined single nucleus transcriptome and open chromatin profiling, we assessed genomic accessibility changes underlying the altered atrial identity expression program, identifying 1846 genomic loci with greater accessibility in control atrial cardiomyocytes compared to KO aCMs. 69% of the control-enriched ATAC regions were bound by TBX5, demonstrating a role for TBX5 in maintaining genomic accessibility. These regions were associated with genes that had higher expression in control aCMs compared to KO aCMs, suggesting they act as TBX5-dependent enhancers. To confirm this hypothesis we analyzed chromatin looping of enhancers marked by H3K27Ac using HiChIP and found 510 chromatin loops that were sensitive to TBX5 dosage. Of the loops enriched in control aCMs, 73.7% contained anchors in control-enriched ATAC regions. Conversely, Tbx5 overexpression in the ventricular myocardium drove atrial gene expression. Together, these data demonstrate a role for TBX5 in maintaining the atrial gene expression program by binding to atrial enhancers to preserve tissue-specific chromatin architecture. We highlight this phenomenon at major atrial identity genes including Nppa, Bmp10 and Myl7. HiChIP for H3K27Ac from atria of TBX5KO and control animals
2023-08-11 | GSE222370 | GEO
Project description:Phospholamban R14del mutazion (PLN-R14del) has been identified in a large family pedigree in which heterozygous carriers exhibited inherited dilated cardiomyopathy (DCM) and death by middle age. To better understand the causal link between the mutations in PLN and DCM pathology, we derived induced pluripotent stem cells from a DCM patient carrying the PLN R14del mutation. We showed that iPSC-derived cardiomyocytes recapitulated the DCM-specific phenotype and demonstrated that either TALEN-mediated genetic correction or combinatorial gene therapy resulted in phenotypic rescue. Our findings offer novel insights into the pathogenesis caused by mutant PLN and point to the development of potential new therapeutics of pathogenic genetic variants associated with inherited cardiomyopathies. iPSCs were derived from a female patient carrying a heterozygous mutation (R14del) in the PLN gene. Tree samples were analyzed: Cardiomyocytes derived from PLN-R41del iPSC cells (R14del-CM); R14del-CMs infected with AAV6-EGFP-miR-PLN and R14del-CMs infected with AAV6-EGFP-miR-luc used as a negative control
2015-02-09 | E-GEOD-65761 | biostudies-arrayexpress
Project description:To investigate the physiological characteristics of cardiomyocytes (CM) in restrictive cardiomyopathy (RCM), we established RCM(heterozygous)-iPSC and produced RCM(homozygous)-iPSC and corrected Isogenic-iPSC using CRISPER-CAS9 technology. Then, we used the RNA-seq data obtained from these three iPSCs and three different healthy iPSC-derived CMs for gene expression profiling analysis.
2023-08-21 | GSE240775 | GEO
Project description:Phospholamban R14del mutazion (PLN-R14del) has been identified in a large family pedigree in which heterozygous carriers exhibited inherited dilated cardiomyopathy (DCM) and death by middle age. To better understand the causal link between the mutations in PLN and DCM pathology, we derived induced pluripotent stem cells from a DCM patient carrying the PLN R14del mutation. We showed that iPSC-derived cardiomyocytes recapitulated the DCM-specific phenotype and demonstrated that either TALEN-mediated genetic correction or combinatorial gene therapy resulted in phenotypic rescue. Our findings offer novel insights into the pathogenesis caused by mutant PLN and point to the development of potential new therapeutics of pathogenic genetic variants associated with inherited cardiomyopathies. Submitter confirms there are no patient privacy concerns with these data. iPSCs were derived from a female patient carrying a heterozygous mutation (R14del) in the PLN gene. Tree samples were analyzed: R14del-CMs (clone L2), corrected R14del-CMs (clone L2GC1) and corrected R14del-CMs (clone L2GC2)
2015-02-09 | E-GEOD-65762 | biostudies-arrayexpress
Project description:BACKGROUND: Brugada syndrome (BrS) is an inherited arrhythmia syndrome caused by loss-of-function variants in the cardiac sodium channel gene SCN5A (sodium voltage-gated channel alpha subunit 5) in ≈20% of subjects. We identified a family with 4 individuals diagnosed with BrS harboring the rare G145R missense variant in the cardiac transcription factor TBX5 (T-box transcription factor 5) and no SCN5A variant. METHODS: We generated induced pluripotent stem cells (iPSCs) from 2 members of a family carrying TBX5-G145R and diagnosed with Brugada syndrome. After differentiation to iPSC-derived cardiomyocytes (iPSC-CMs), electrophysiologic characteristics were assessed by voltage- and current-clamp experiments (n=9 to 21 cells per group) and transcriptional differences by RNA sequencing (n=3 samples per group), and compared with iPSC-CMs in which G145R was corrected by CRISPR/Cas9 approaches. The role of platelet-derived growth factor (PDGF)/phosphoinositide 3-kinase (PI3K) pathway was elucidated by small molecule perturbation. The rate-corrected QT (QTc) interval association with serum PDGF was tested in the Framingham Heart Study cohort (n=1893 individuals). RESULTS: TBX5-G145R reduced transcriptional activity and caused multiple electrophysiologic abnormalities, including decreased peak and enhanced “late” cardiac sodium current (INa), which were entirely corrected by editing G145R to wildtype. Transcriptional profiling and functional assays in genome-unedited and -edited iPSC-CMs showed direct SCN5A downregulation caused decreased peak INa, and that reduced PDGF receptor (PDGFRA [platelet-derived growth factor receptor α]) expression and blunted signal transduction to PI3K was implicated in enhanced late INa. Tbx5 regulation of the PDGF axis and increased arrhythmia risk with disruption of PDGF sigaling were both conserved in murine model systems. PDGF receptor blockade markedly prolonged normal iPSC-CM action potentials and plasma levels of PDGF in the Framingham Heart Study were inversely correlated with the QTc interval (P
2022-12-31 | GSE221945 | GEO
Project description:Gene expression analysis, a) comparing isogenic karyotypically normal iPSCs to del7q-iPSCs, b) comparing del7q-iPSCs to spontaneously corrected iPSCs. The chr7q deletion results in reduced expression levels of a large number of genes in the chr7q deleted region Two-condition experiment, del7q-iPSCs vs. isogenic normal iPSCs and del7q-iPSCs vs spontaneously corrected-iPSCs. Biological replicates: 3 control replicates, 3 del7q-iPSC replicates and 3 spontaneously corrected-iPSC replicates
2015-02-16 | E-GEOD-65215 | biostudies-arrayexpress
Project description:We deep sequenced wildtype and Tbx5-mutant mouse atria, identifying ~2600 novel Tbx5-dependent ncRNAs. Tbx5-dependent ncRNA transcription provided a quantitative metric of Tbx5-dependent enhancer activity, correlating with target gene expression.
2023-08-02 | GSE239805 | GEO