Transcriptomic analysis of cultured isogenic myotonic dystrophy type 1 myoblasts with and without the DMPK CTG repeat
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE127296 | GEO | 2019/04/11
REPOSITORIES: GEO
Similar Datasets
Project description:The congenital form of myotonic dystrophy type 1 (cDM) is caused by large-scale expansion of a (CTG•CAG)n repeat in DMPK and DM1-AS. Production of toxic transcripts with long trinucleotide tracts from these genes results in impediment of myogenic differentiation capacity as cDM’s most prominent morpho-phenotypic hallmark. In the current in vitro study, we compared the early differentiation programs of isogenic cDM myoblasts with and without a (CTG)2600 repeat obtained by gene editing. We found that excision of the repeat restored the ability of cDM myoblasts to engage in myogenic fusion, preventing that the ensuing myotubes remained immature. Although the cDM-typical epigenetic status of the DM1 locus and the expression of genes therein were not altered upon removal of the repeat, analyses at the transcriptome and proteome level revealed that early abnormalities in the temporal expression of differentiation regulators, myogenic progression markers and alternative splicing patterns before and immediately after the onset of differentiation became normalized. Our observation that molecular and cellular features of cDM are reversible and can be corrected by repeat-directed genome editing in muscle progenitors is important information for future development of gene therapy for different forms of DM1.
2019-11-20 | PXD016056 | Pride
Project description:Transcriptomic analysis of cultured isogenic myotonic dystrophy type 1 myoblasts with and without the DMPK CTG repeat
| PRJNA524687 | ENA
Project description:This study tested candidate therapeutic antimiRs in a comprehensive new collection of primary myoblasts derived from myotonic dystrophy type 1 (DM1) patients. DM1 is caused by genetically unstable CTG repeat expansions in the DMPK gene and has multiple clinical presentations, likely because of variable repeat sizes at the tissue and organ levels. Expanded DMPK transcripts deplete Muscleblind-Like Splicing Regulator protein MBNL1, which in turn causes DM1 symptoms. A promising therapeutic approach increases the expression of MBNL1 by blocking natural repressors miR-23b and miR-218 employing antimiRs with chemical modifications designed for a better pharmacological profile in humans. In untreated primary cells, we demonstrate that upregulated therapeutic targets miR-23b and miR-218 and reduced MBNL1 protein levels inversely correlate with CTG repeat size, supporting that active MBNL1 protein repression synergizes with the sequestration by CUG repeats in DM1. Upon treatment with novel antimiRs, multiple readouts of RNA toxicity associated with typical DM1 alterations improved. MBNL1-dependent exon inclusions, and myoblast fusion and myotube area defects, showed robust correction over a wide range of CTG expansions. Unexpectedly, antimiR treatment also reduced DMPK transcript levels and the number of ribonuclear aggregates. Based on these data, we selected a leading antimiR for further transcriptomics characterization and demonstrated that it reversed up to 68% of dysregulated genes. The study revealed that the candidate antimiRs could provide therapy to clinically relevant DM1 forms over a wide range of repeat sizes and genetic backgrounds by simultaneously reducing MBNL1 sequestration and derepressing protein synthesis.
2024-05-01 | GSE237411 | GEO
Project description:Expanded CAG/CTG repeats underlie thirteen neurological disorders, including myotonic dystrophy type 1 (DM1) and Huntington’s disease (HD). Upon expansion, CAG/CTG repeat loci acquire heterochromatic characteristics. This observation raises the hypothesis that repeat expansion provokes changes to higher-order chromatin conformation and thereby affects both gene expression in cis and the genetic instability of the repeat tract. Here we tested this hypothesis directly by performing 4C sequencing at the DMPK and HTT loci from DM1 and HD patient-derived cells. Surprisingly, chromatin contacts remain unchanged upon repeat expansion at both loci. This was true for expanded alleles with different DNA methylation levels and CTCF binding. Repeat tract sizes ranging from 15 to 1,700 repeats displayed strikingly similar chromatin interaction profiles. Moreover, the ectopic insertion of an expanded CAG repeat tract did not change the three-dimensional chromatin conformation of the surrounding genomic region. Our findings argue that extensive changes in heterochromatic properties are not enough to alter chromatin conformation at expanded CAG/CTG repeat loci. We conclude that 3D chromatin conformation is unlikely to drive repeat expansions or changes in gene expression in expanded CAG/CTG repeat disorders. This SuperSeries is composed of the SubSeries listed below.
2020-04-07 | GSE148185 | GEO
Project description:Bisulfite sequencing was performed on GM04604 (UN-B), GM06077 (DM1-A), and GM04648 (DM1-B) patient cells to determine the levels of CpG methylation present at two CTCF sites closely flanking the CTG repeats of DMPK.
2020-04-07 | GSE148177 | GEO
Project description:Expanded CAG/CTG repeats underlie thirteen neurological disorders, including myotonic dystrophy type 1 (DM1) and Huntington’s disease (HD). Upon expansion, CAG/CTG repeat loci acquire heterochromatic characteristics. This observation raises the hypothesis that repeat expansion provokes changes to higher-order chromatin conformation and thereby affects both gene expression in cis and the genetic instability of the repeat tract. Here we tested this hypothesis directly by performing 4C sequencing at the DMPK and HTT loci from DM1 and HD patient-derived cells. Surprisingly, chromatin contacts remain unchanged upon repeat expansion at both loci. This was true for expanded alleles with different DNA methylation levels and CTCF binding. Repeat tract sizes ranging from 15 to 1,700 repeats displayed strikingly similar chromatin interaction profiles. Moreover, the ectopic insertion of an expanded CAG repeat tract did not change the three-dimensional chromatin conformation of the surrounding genomic region. Our findings argue that extensive changes in heterochromatic properties are not enough to alter chromatin conformation at expanded CAG/CTG repeat loci. We conclude that 3D chromatin conformation is unlikely to drive repeat expansions or changes in gene expression in expanded CAG/CTG repeat disorders.
2020-04-07 | GSE148176 | GEO
Project description:Myotonic dystrophy type 1 (DM1), the most frequent inherited muscular dystrophy in adults, is caused by the CTG repeat expansion in the 3’UTR of the DMPK gene. Mutant DMPK RNA accumulates in nuclear foci altering diverse cellular functions including alternative splicing regulation. DM1 is a multisystemic condition, with debilitating central nervous system alterations. Although a defective neuroglia communication has been described as a contributor of the brain pathology in DM1, the specific cellular and molecular events potentially affected in glia cells have not been totally recognized. Thus, to study the effects of DM1 mutation on glial physiology, in this work we have established an inducible DM1 model derived from the MIO-M1 cell line expressing 648 CUG repeats. This new model recreated the molecular hallmarks of DM1 elicited by a toxic RNA gain-of-function mechanism: accumulation of RNA foci colocalized with MBNL proteins and dysregulation of alternative splicing. By applying a microarray whole-transcriptome approach, we identified several gene changes associated with DM1 mutation in MIO-M1 cells, including the immune mediators CXCL10, CCL5, CXCL8, TNFAIP3, and TNFRSF9, as well as the microRNAs miR-222, miR-448, among others, as potential regulators. A gene ontology enrichment analyses revealed that inflammation and immune response emerged as major cellular deregulated processes in the MIO-M1 DM1 cells. Our findings indicate the involvement of an altered immune response in glia cells, opening new windows for the study of glia as potential contributor of the CNS symptoms in DM1. In this dataset, we include the expression data obtained from MIO-M1-CTG(648) and MIO-M1-CTG(0) with and witouth Doxycycline treatment (1µg/ml) by 8 days . These data are used to obtain genes that are differentially expressed in response to mutant (CUG expanded) DMPK RNA expression.
2023-10-31 | GSE164057 | GEO
Project description:Myotonic dystrophy type 1 (DM1) is an autosomal dominant inherited disorder caused by expansion of a germline and somatically unstable CTG repeat in the DMPK gene. Previously, CTG repeat length at birth has been correlated to patient age at symptom onset. Attempts to correlate CTG repeat length with progressive DM1 phenotypes, such as muscle power, have proven difficult. To better correlate genotype with progressive phenotypes, we have measured CTG repeat tract length and screened for interrupting variant repeats in 192 study participants from a well-characterized Canadian cohort. We have assessed genotype-phenotype correlations with nine progressive measures of skeletal muscle power and respiratory function. We have built statistical models that include confounding factors such as sex, age, height and weight to further explain variation in muscle power. Our analysis reveals a strong correlation between DM1 genotype and respiratory function and skeletal muscle power, as part of a complex model that includes additional modulators such as sex, age, height, weight and the presence or absence of interrupting variant repeats. Distal skeletal muscle measurements, such as hand pinch and grip strength, show the strongest correlation with disease genotype. Detailed analysis of CTG repeat length, and incorporation of confounding factors, greatly improves the predictive ability of these models. They reveal a greater genetic influence on individual progressive phenotypes than on age at symptom onset and for clinical trials will help optimize stratification and explain patient variability. They will also help practitioners prioritize assessment of the muscular power measurements that correlate best with disease severity.
| S-EPMC6586140 | biostudies-literature
Project description:Short tandem repeats (STRs) are prone to expansion mutations that cause multiple hereditary neurological and neuromuscular diseases. To study pathomechanisms using mouse models that recapitulate the tissue specificity and developmental timing of an STR expansion gene, we used rolling circle amplification and CRISPR/Cas9-mediated genome editing to generate Dmpk CTG expansion (CTGexp) knockin models of myotonic dystrophy type 1 (DM1). We demonstrate that skeletal muscle myoblasts and brain choroid plexus epithelial cells are particularly susceptible to Dmpk CTGexp mutations and RNA mis-splicing. Our results implicate dysregulation of muscle regeneration and cerebrospinal fluid homeostasis as early pathogenic events in DM1.
2019-11-15 | GSE137494 | GEO
Project description:Myotonic dystrophy type 1 is a dominantly inherited multisystemic disease caused by CTG tandem repeat expansions in the DMPK 3' untranslated region. These expanded repeats are transcribed and produce toxic CUG RNAs that sequester and inhibit activities of the MBNL family of developmental RNA processing factors. Although myotonic dystrophy is classified as a muscular dystrophy, the brain is also severely affected by an unusual cohort of symptoms, including hypersomnia, executive dysfunction, as well as early onsets of tau/MAPT pathology and cerebral atrophy. To address the molecular and cellular events that lead to these pathological outcomes, we recently generated a mouse Dmpk CTG expansion knockin model and identified choroid plexus epithelial cells as particularly affected by the expression of toxic CUG expansion RNAs. To determine if toxic CUG RNAs perturb choroid plexus functions, alternative splicing analysis was performed on lateral and hindbrain choroid plexi from Dmpk CTG knockin mice. Choroid plexus transcriptome-wide changes were evaluated in Mbnl2 knockout mice, a developmental-onset model of myotonic dystrophy brain dysfunction. To determine if transcriptome changes also occurred in the human disease, we obtained post-mortem choroid plexus for RNA-seq from donors without neurologically unaffected (two females, three males; ages 50-70) and myotonic dystrophy type 1 donors (one female, three males; ages 50-70). To test that choroid plexus transcriptome alterations resulted in altered CSF composition, we obtained CSF via lumbar puncture from patients with myotonic dystrophy type 1 (five females, five males; ages 35-55) and non-myotonic dystrophy patients (three females, four males; ages 26-51) and Western blot and osmolarity analyses were used to test CSF alterations predicted by choroid plexus transcriptome analysis. We determined that CUG RNA induced toxicity was more robust in the lateral choroid plexus of Dmpk CTG knockin mice due to comparatively higher Dmpk and lower Mbnl RNA levels. Impaired transitions to adult splicing patterns during choroid plexus development were identified in Mbnl2 knockout mice, including mis-splicing previously found in Dmpk CTG knockin mice. Whole transcriptome analysis of myotonic dystrophy type 1 choroid plexus revealed disease-associated RNA expression and mis-splicing events. Based on these RNA changes, predicted alterations in ion homeostasis, secretory output, and CSF composition were confirmed by analysis of myotonic dystrophy type 1 CSF. Our results implicate choroid plexus spliceopathy and concomitant alterations in CSF homeostasis as an unappreciated contributor to myotonic dystrophy type 1 CNS pathogenesis.
2023-07-03 | GSE228314 | GEO