Effect of the Mutated p.H222P A-type Lamins on Gene Expression in Both Patient-Derived Cardiomyocytes and Mouse Models of Dilated Cardiomyopathy
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus Homo sapiens
PROVIDER: GSE289418 | GEO | 2025/02/17
REPOSITORIES: GEO
Similar Datasets
Project description:• Mutations in the LMNA gene encoding Lamin A and C (Lamin A/C), major components of the nuclear lamina, cause laminopathies including dilated cardiomyopathy (DCM), but the underlying molecular mechanisms have not been fully elucidated. Here, by leveraging single-cell RNA-seq, ATAC-seq, protein array, and electron microscopy analysis, we show that insufficient structural maturation of cardiomyocytes owing to trapping of transcription factor TEAD1 by mutant Lamin A/C at the nuclear membrane underlies the pathogenesis of Q353R- LMNA-related DCM. Inhibition of the Hippo pathway rescued the dysregulation of cardiac developmental genes by TEAD1 in LMNA-mutant cardiomyocytes. Single-cell RNA-seq of cardiac tissues from DCM patients with the LMNA mutation confirmed the dysregulated expression of TEAD1 target genes. Our results propose an intervention for transcriptional dysregulation as a potential treatment of LMNA-related DCM.
2023-03-06 | GSE190977 | GEO
Project description:Lamin A/C proteins, encoded by the LMNA gene, are intermediate filament proteins of the nuclear lamina, and predominantly expressed in differentiated cells including cardiomyocytes. Mutations in LMNA are associated with laminopathies, congenital diseases affecting muscle and homeostasis. One of the laminopathies associated with a missense mutation (N195K) in the A-type lamins results in dilated cardiomyopathy (DCM) with arrhythmias and sudden death. However it is unknown how the mutation in this LMNA gene contributes to the mechanism of arrhythmia and sudden death. To investigate this a mouse line expressing the Lmna-N195K (LmnaN195K/N195K) was used. Mutant mice demonstrated reduced fractional shortening, LV mass, wall thickness and dilated cardiomyopathy by echocardiography at 6 weeks consistent with human DCM, and died at an early age (6-7 weeks). Comparative cDNA microarray analysis from LmnaN195K/N195K and the wild type (WT) control ventricles at 6 weeks age revealed significant alterations in the expression of ion channels, transporter proteins, caveolins and associated proteins such as MAP kinases. Transmission electron microscopy analysis showed structural alterations of the ventricular myocytes with increase in number of caveolae. Quantitative Western blot analysis confirmed reduced expression for Cavβ (2 fold) subunits of the L-type Ca2+ channel. In contrast the expression levels of Cav3 (2.5 fold) was significantly increased. To investigate the functional impact of Lmna N195K on the ICa,L, we transiently expressed either the WT LMNA+GFP, Lmna N195K+GFP or GFP (control) in isolated neonatal mouse ventricular myocytes and performed whole cell patch clamp analysis. Transient expression of Lmna N195K significantly reduced (58 %) peak ICa,L (-6.0 ± 2 pA/pF, n=9) compared to GFP control (-14 ± 2 pA/pF, n=8). Expression of WT LMNA did not affect the ICa,L (-14.2 ± 2.5 pA/pF, n=8) compared to control. Conclusion: We conclude that Lmna N195K mutation results in reduced expression of ion channels and scaffolding proteins in the left ventricle with a significant reduction in peak ICa,L in ventricular myocytes and these may contribute to the mechanism of arrhythmia and dilated cardiomyopathy. 6 samples
2012-05-31 | E-GEOD-36502 | biostudies-arrayexpress
Project description:Lamin A/C proteins, encoded by the LMNA gene, are intermediate filament proteins of the nuclear lamina, and predominantly expressed in differentiated cells including cardiomyocytes. Mutations in LMNA are associated with laminopathies, congenital diseases affecting muscle and homeostasis. One of the laminopathies associated with a missense mutation (N195K) in the A-type lamins results in dilated cardiomyopathy (DCM) with arrhythmias and sudden death. However it is unknown how the mutation in this LMNA gene contributes to the mechanism of arrhythmia and sudden death. To investigate this a mouse line expressing the Lmna-N195K (LmnaN195K/N195K) was used. Mutant mice demonstrated reduced fractional shortening, LV mass, wall thickness and dilated cardiomyopathy by echocardiography at 6 weeks consistent with human DCM, and died at an early age (6-7 weeks). Comparative cDNA microarray analysis from LmnaN195K/N195K and the wild type (WT) control ventricles at 6 weeks age revealed significant alterations in the expression of ion channels, transporter proteins, caveolins and associated proteins such as MAP kinases. Transmission electron microscopy analysis showed structural alterations of the ventricular myocytes with increase in number of caveolae. Quantitative Western blot analysis confirmed reduced expression for Cavβ (2 fold) subunits of the L-type Ca2+ channel. In contrast the expression levels of Cav3 (2.5 fold) was significantly increased. To investigate the functional impact of Lmna N195K on the ICa,L, we transiently expressed either the WT LMNA+GFP, Lmna N195K+GFP or GFP (control) in isolated neonatal mouse ventricular myocytes and performed whole cell patch clamp analysis. Transient expression of Lmna N195K significantly reduced (58 %) peak ICa,L (-6.0 ± 2 pA/pF, n=9) compared to GFP control (-14 ± 2 pA/pF, n=8). Expression of WT LMNA did not affect the ICa,L (-14.2 ± 2.5 pA/pF, n=8) compared to control. Conclusion: We conclude that Lmna N195K mutation results in reduced expression of ion channels and scaffolding proteins in the left ventricle with a significant reduction in peak ICa,L in ventricular myocytes and these may contribute to the mechanism of arrhythmia and dilated cardiomyopathy.
2012-06-01 | GSE36502 | GEO
Project description:Lamins are type V intermediate filament proteins underlying the inner nuclear membrane which provide structural rigidity to the nucleus, tether the chromosomes and maintain nuclear homeostasis. Studies have identified developmentally regulated regions of the genome that are dynamically associated with the nuclear lamina. A large number of mutations in LMNA gene encoding lamin A/C results in a wide array of human diseases, collectively termed as laminopathies. Dilated Cardiomyopathy (DCM) is one such cardiovascular disease which is associated with systolic dysfunction of left or both ventricles leading to cardiac arrhythmia culminating into myocardial infarction. In this work, we have unravelled the gene expression by RNA Sequencing analysis in mouse myoblast cell line in the context of the missense mutation LMNA 289A>G (Lys97Glu) that is found in DCM afflicted patients with severe symptoms.
2022-06-26 | GSE206759 | GEO
Project description:To investigate the molecular basis for male-specific steatohepatitis in Lamin A/C-deficient livers, microarray gene expression analysis was performed on total liver RNA isolated from 26- to 39-week-old, male LMNA+/+, LMNA flx/+, and LMNA flx/flx; Alb-Cre+ C57BL/6 mice fed either normal chow (NC) or high fat diet plus carbohydrate-supplemented water (HFD). Lamins are nuclear intermediate filament proteins that comprise the major components of the nuclear lamina in metazoan cells. Mutations in LMNA, which encodes lamins A/C, cause diseases termed laminopathies, including lipodystrophy, cardiomyopathy, and premature aging. The lamin A/C mutation-associated Dunnigan familial partial lipodystrophy is typically accompanied by fatty liver disease. The role of lamins in the liver is unknown, and it is unclear whether laminopathy-associated liver disease is due to primary hepatocyte defects or systemic alterations. To address these questions, mice carrying a hepatocyte-specific deletion of Lmna (KO mice) were generated. KO hepatocytes manifested abnormal nuclear morphology, and KO mice developed spontaneous male-selective hepatosteatosis, with increased susceptibility to high fat diet-induced steatohepatitis and fibrosis. The molecular mechanism by which liver-specific Lamin A/C deficiency induces male-specific steatohepatitis is unknown. The microarray data presented here demonstrates that hepatic Lmna deficiency is associated with upregulated expression of fatty acid transporters, lipid biosynthetic enzymes, lipid-droplet associated proteins, and interferon-regulated genes and other pro-inflammatory mediators.
2017-01-16 | GSE93643 | GEO
Project description:Mutations in the LMNA gene causes set of disorders collectively referred to as laminopathies that include dilated cardiomyopathy. Lamin A/C proteins a components of nuclear lamina forms distinct nuclear domains called lamina associated domains (LADs). The roles of LADs in DCM is not known. To identify LADs and characterize their associations with CpG methylation and gene expression in human cardiac myocytes isolated from patients with DCM and controls we performed Chromatin immunoprecipitation-sequencing (ChIP-Seq), reduced representative bisulfite sequencing (RRBS), and RNA-sequencing (RNA-Seq) in 5 control and 5 DCM hearts with defined pathogenic variants in the LMNA gene. LADs are redistributed in DCM, are associated with CpG methylation and suppressed transcription, contributing to the pathogenesis of DCM in laminopathies.
2019-03-12 | GSE120837 | GEO
Project description:Mutations in the LMNA gene causes set of disorders collectively referred to as laminopathies that include dilated cardiomyopathy. Lamin A/C proteins a components of nuclear lamina forms distinct nuclear domains called lamina associated domains (LADs). The roles of LADs in DCM is not known. To identify LADs and characterize their associations with CpG methylation and gene expression in human cardiac myocytes isolated from patients with DCM and controls we performed Chromatin immunoprecipitation-sequencing (ChIP-Seq), reduced representative bisulfite sequencing (RRBS), and RNA-sequencing (RNA-Seq) in 5 control and 5 DCM hearts with defined pathogenic variants in the LMNA gene. LADs are redistributed in DCM, are associated with CpG methylation and suppressed transcription, contributing to the pathogenesis of DCM in laminopathies.
2019-03-12 | GSE120836 | GEO
Project description:Mutations in the LMNA gene encoding nuclear lamins A/C cause a diverse array of tissue-selective diseases, with the heart being the most commonly affected organ. Despite progress in understanding the molecular perturbations emanating from LMNA mutations, an integrative understanding of the pathogenesis leading to cardiac dysfunction remains elusive. Using a novel cell-type specific Lmna deletion mouse model capable of translatome profiling, we found that cardiomyocyte-specific Lmna deletion in adult mice led to rapid cardiomyopathy with pathological remodeling. Prior to the onset of cardiac dysfunction, lamin A/C-depleted cardiomyocytes displayed nuclear envelope deterioration, disruption of the ER-golgi interface, and ER stress. Translatome profiling identified upregulation of Med25, a transcriptional co-factor involved in unfolded protein responses. Culturing Lmna-deleted cardiomyocytes in stiff hydrogels recapitulated these pathological features, confirming that cardiomyocyte-extrinsic factors contribute to the pathogenesis. Pharmacological activation of autophagy or modulation of ER stress significantly improved the cardiac function. These studies support a unified hypothesis wherein cardiomyopathy develops from autophagic impairment that exacerbates ER stress emanating from nuclear envelope deterioration.
2022-10-11 | GSE185620 | GEO
Project description:Lamins are the major structural components of the nuclear lamina (NL) beneath the inner nuclear membrane. Although lamins are believed to regulate genome organization and transcription, how they perform these functions remains poorly understood. Combining Hi-C with fluorescence in situ hybridization (FISH) and Histone and Lamina landscape (HiLands) analyses of chromatin domains, we show that lamins differentially regulate the NL-associated HiLands-P and -B domains in mouse ES cells (mESCs). Lamin loss leads to HiLands-P expansion at the NL, detachment of HiLands-B from the NL, and genome-wide changes of 3D chromatin interactions in NL-associated and interior HiLands in mESCs. Further epigenome and transcriptome analyses show that lamins can function from the NL to maintain the boundaries of active and repressive chromatin domains, thereby influencing gene expression throughout the genome. These findings should provide the basis to further understand how changes in the NL-associated chromatin influence transcription in development and NL-associated diseases.
2017-11-01 | GSE89520 | GEO
Project description:Mutations in LMNA, encoding Lamin A/C, lead to a variety of diseases known as laminopathies that include dilated cardiomyopathy (DCM). The role of epigenetic mechanisms. such as DNA methylation, has not been thoroughly investigated. Furthermore, the impact of patient-specific LMNA mutations on DNA methylation is unknown. To explore the role of DNA methylation in the context of unique LMNA mutations, we performed reduced representation bisulfite sequencing (RRBS) on ten pairs of fibroblasts and their induced pluripotent stem cell (iPSC) derivatives from two families with DCM due to distinct LMNA mutations. Family-specific differentially methylated regions (DMRs) were identified by comparing the DNA methylation landscape of patient and control samples. Fibroblast DMRs were found to enrich for distal regulatory features and transcriptionally repressed chromatin and to associate with genes related to phenotypes found in laminopathies. These DMRs, in combination with transcriptome-wide expression data and Lamina-associated domain (LAD) organization, revealed the presence of inter-family epimutation hotspots near differentially expressed genes, most of which were located near redistributed LADs. Comparison of DMRs found in fibroblasts and iPSCs identified regions where epimutations were persistent across both cell types. Finally, a network of disease-associated genes dysregulated in LMNA mutated cells was uncovered, potentially due to aberrant methylation changes. In conclusion, the use of in vitro culture models of patient-derived cells and differential methylation analysis enabled the identification of epimutation hotspots and dysregulated genes, consistent with a Lamin A/C mutation-specific epigenetic disease mechanism that arose in somatic and early-developmental cell stages.
2021-07-20 | GSE164365 | GEO