Reversal of RNA toxicity in myotonic dystrophy via a decoy RNA-binding protein with high affinity for expanded CUG repeats [human]
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE189503 | GEO | 2022/01/03
REPOSITORIES: GEO
Similar Datasets
Project description:Myotonic dystrophy type 1 (DM1) is an RNA-dominant disease whose pathogenesis stems from the functional loss of muscleblind-like RNA-binding proteins (RBPs), which causes the formation of alternative-splicing defects. The loss of functional muscleblind-like protein 1 (MBNL1) results from its nuclear sequestration by mutant transcripts containing pathogenic expanded CUG repeats (CUGexp). Here we show that an MBNL1∆ RBP engineered to act as a decoy for CUGexp reverses the toxicity of the mutant transcripts.
2022-01-03 | GSE189515 | GEO
Project description:Myotonic dystrophy type 1 (DM1) is an RNA dominant disease in which mutant transcripts containing an expanded CUG repeat (CUGexp) cause muscle dysfunction by interfering with biogenesis of other mRNAs. The toxic effects of mutant RNA are mediated partly through sequestration of splicing regulator Muscleblind-like 1 (Mbnl1), a protein that binds to CUGexp RNA. A gene that is prominently affected encodes chloride channel 1 (Clcn1), resulting in hyperexcitability of muscle (myotonia). To identify DM1-affected genes and study mechanisms for dysregulation, we performed global mRNA profiling in transgenic mice that express CUGexp RNA, as compared to Mbnl1 knockout and Clcn1 null mice. We found that the majority of changes induced by CUGexp RNA in skeletal muscle can be explained by reduced activity of Mbnl1, including many changes that are secondary to myotonia. The pathway most affected comprises genes involved in calcium signaling and homeostasis. Some effects of CUGexp RNA on gene expression are caused by abnormal alternative splicing or downregulation of Mbnl1-interacting mRNAs. However, several of the most highly dysregulated genes showed altered transcription, as indicated by parallel changes of the corresponding premRNAs. These results support the idea that trans-dominant effects of CUGexp RNA on gene expression in this transgenic model may occur at the level of transcription, RNA processing, and mRNA decay, and are mediated mainly but not entirely through sequestration of Mbnl1. Experiment Overall Design: All experiments involved generating expression profiles of quadriceps muscles taken from mice. Experiments 1 and 2: samples were hybridized to Moe430A and Moe430B arrays. Experiment 3: samples were hybridized to Mouse Genome 430 2.0 array. Experiment 1 compared expression profiles of wild-type mice (FVB strain) with two lines, designated 20b and 41, of CUGexp transgenic mice with FVB background. Experiment 2 compared expression profiles of Clcn1-null (myotonic) mice with the wild-type background strain (BALB). Experiment 3 compared expression profiles of Mbnl1-null mice with the wild-type background strain (FVB).
2009-02-13 | E-GEOD-14691 | biostudies-arrayexpress
Project description:Distinct RNA-mediated impacts on alternative splicing and extracellular matrix gene expression in a mouse model of myotonic dystrophy. Myotonic dystrophy (DM1) is associated with expression of expanded CTG DNA repeats as RNA (CUGexp RNA). To test whether CUGexp RNA creates a global splicing defect, we compared skeletal muscle of two mouse DM1 models, one expressing a CTGexp transgene, and another homozygous for a defective Mbnl1 gene. Strong correlation in splicing changes for ~100 new Mbnl1-regulated exons indicates loss of Mbnl1 explains >80% of the splicing pathology due to CUGexp RNA. In contrast, only about half of mRNA level changes can be attributed to loss of Mbnl1, indicating CUGexp RNA has Mbnl1-independent effects, particularly on mRNAs for extracellular matrix (ECM) proteins. We propose that CUGexp RNA causes two separate effects: loss of Mbnl1 function, disrupting splicing, and loss of another function that disrupts ECM mRNA regulation, possibly mediated by MBNL2. These findings reveal unanticipated similarities between DM1 and other muscular dystrophies. MBNL1 knockout and HSALR mice on FVB background. To test whether CUGexp RNA creates a global splicing defect, we compared skeletal muscle of two mouse DM1 models, one expressing a CTGexp transgene, and another homozygous for a defective Mbnl1 gene. These samples were compared to the skeletal muscle of a wildtype mouse.
2010-01-23 | E-GEOD-17986 | biostudies-arrayexpress
Project description:Myotonic dystrophy type 1 (DM1) is an RNA dominant disease in which mutant transcripts containing an expanded CUG repeat (CUGexp) cause muscle dysfunction by interfering with biogenesis of other mRNAs. The toxic effects of mutant RNA are mediated partly through sequestration of splicing regulator Muscleblind-like 1 (Mbnl1), a protein that binds to CUGexp RNA. A gene that is prominently affected encodes chloride channel 1 (Clcn1), resulting in hyperexcitability of muscle (myotonia). To identify DM1-affected genes and study mechanisms for dysregulation, we performed global mRNA profiling in transgenic mice that express CUGexp RNA, as compared to Mbnl1 knockout and Clcn1 null mice. We found that the majority of changes induced by CUGexp RNA in skeletal muscle can be explained by reduced activity of Mbnl1, including many changes that are secondary to myotonia. The pathway most affected comprises genes involved in calcium signaling and homeostasis. Some effects of CUGexp RNA on gene expression are caused by abnormal alternative splicing or downregulation of Mbnl1-interacting mRNAs. However, several of the most highly dysregulated genes showed altered transcription, as indicated by parallel changes of the corresponding premRNAs. These results support the idea that trans-dominant effects of CUGexp RNA on gene expression in this transgenic model may occur at the level of transcription, RNA processing, and mRNA decay, and are mediated mainly but not entirely through sequestration of Mbnl1. Keywords: comparison of normal and transgenic mice
2009-02-05 | GSE14691 | GEO
Project description:Myotonic dystrophy type 1 (DM1) is an incurable neuromuscular disorder caused by an expanded CTG repeat that is transcribed into r(CUG)exp. The RNA repeat expansion sequesters regulatory proteins such as Muscleblind-like protein 1 (MBNL1), which causes pre-mRNA splicing defects. The disease-causing r(CUG)exp has been targeted by antisense oligonucleotides, CRISPR-based approaches, and RNA-targeting small molecules. Herein, we describe a designer small molecule, Cugamycin, that targets the structure of r(CUG)exp and cleaves it in cells and in vivo. Cugamycin selectively cleaves r(CUG)exp while leaving short repeats of r(CUG) untouched. In contrast, oligonucleotides that recognize r(CUG) sequence rather than structure cleave both long and short r(CUG)-containing transcripts. In the HSALR mouse model of DM1, Cugamycin selectively ablates r(CUG)exp in disease-affected muscle. Transcriptomic, histological, and phenotypic studies demonstrate that Cugamycin broadly and specifically relieves DM1-associated defects without detectable off-targets. Thus, small molecules that bind and cleave RNA may have utility as lead chemical probes and medicines.
2019-03-22 | GSE127809 | GEO
Project description:Myotonic dystrophy type 1 (DM1) is a dominantly inherited disorder due to a toxic gain of function of RNA transcripts containing expanded CUG repeats (CUGexp). Patients with DM1 present with multisystemic symptoms, such as muscle wasting, cognitive impairment, cataract, frontal baldness, and endocrine defects, which resemble accelerated aging. Although the involvement of cellular senescence, a critical component of aging, was suggested in studies of DM1 patient-derived cells, the detailed mechanism of cellular senescence caused by CUGexp RNA remains unelucidated. Here, we developed a DM1 cell model that conditionally expressed CUGexp RNA in human primary cells so that we could perform a detailed assessment that eliminated the variability in primary cells from different origins. To identify the pathway that induced cellular senescence, we conducted comprehensive gene expression analysis using RNA sequencing (RNA-Seq) in CUGexp+ and CUGexp− cells.
2022-04-19 | GSE196265 | GEO
Project description:Distinct RNA-mediated impacts on alternative splicing and extracellular matrix gene expression in a mouse model of myotonic dystrophy. Myotonic dystrophy (DM1) is associated with expression of expanded CTG DNA repeats as RNA (CUGexp RNA). To test whether CUGexp RNA creates a global splicing defect, we compared skeletal muscle of two mouse DM1 models, one expressing a CTGexp transgene, and another homozygous for a defective Mbnl1 gene. Strong correlation in splicing changes for ~100 new Mbnl1-regulated exons indicates loss of Mbnl1 explains >80% of the splicing pathology due to CUGexp RNA. In contrast, only about half of mRNA level changes can be attributed to loss of Mbnl1, indicating CUGexp RNA has Mbnl1-independent effects, particularly on mRNAs for extracellular matrix (ECM) proteins. We propose that CUGexp RNA causes two separate effects: loss of Mbnl1 function, disrupting splicing, and loss of another function that disrupts ECM mRNA regulation, possibly mediated by MBNL2. These findings reveal unanticipated similarities between DM1 and other muscular dystrophies.
2010-01-24 | GSE17986 | GEO
Project description:Myotonic dystrophy type 1 (DM1) is a dominantly inherited disease that affects multiple organ systems. Cardiac dysfunction is the second leading cause of death in DM1. We quantified gene expression in heart tissue from a heart-specific DM1 mouse model (EpA960/MCM) which inducibly expresses human DMPK exon 15 containing 960 CUG expanded repeats and that reproduced Celf1 up regulation. To assess if, in addition to splicing and miRNA defects, CUGexp RNA also perturbed the steady state mRNA levels of genes, we carried out a microarray study on wildtype E14, adult, MCM controls and DM1 mouse hearts. As anticipated we noted a large number of genes to be developmentally regulated in wildtype hearts, however, within 72h of induction of CUGexp RNA there appeared to be a coordinate adult-to-embryonic shift in steady state levels of many genes. We identified transcripts over-expressed or under-expressed in hearts of wildtype adult mice, wildtype embryonic day 14 (E14), and DM1 mice induced to express CUGexp RNA for 72h and 1wk, when compared to MCM controls. Multiple group comparison.
2014-01-24 | E-GEOD-48991 | biostudies-arrayexpress
Project description:Myotonic dystrophy type 1 (DM1) is a dominantly inherited disease that affects multiple organ systems. Cardiac dysfunction is the second leading cause of death in DM1. We quantified gene expression in heart tissue from a heart-specific DM1 mouse model (EpA960/MCM) which inducibly expresses human DMPK exon 15 containing 960 CUG expanded repeats and that reproduced Celf1 up regulation. To assess if, in addition to splicing and miRNA defects, CUGexp RNA also perturbed the steady state mRNA levels of genes, we carried out a microarray study on wildtype E14, adult, MCM controls and DM1 mouse hearts. As anticipated we noted a large number of genes to be developmentally regulated in wildtype hearts, however, within 72h of induction of CUGexp RNA there appeared to be a coordinate adult-to-embryonic shift in steady state levels of many genes.
2014-01-24 | GSE48991 | GEO
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