Project description:Crossing of hDMD mice that contain the full-length 2.3 Mb hDMD gene were crossed with dystrophin-deficient mdx mice and dystrophin and utrophin double-deficient mdx x utrn-/- mice resulted in a full rescue of the dystrophic features of these mice, as concluded from histological analysis. Analysis on Affymetrix gene chips demonstrated that also expression profiles of the dystrophic mice were normalized by crossing with transgenic hDMD mice. This confirms the full functionality of the hDMD transgene in mice. Keywords: disease state analysis
Project description:Crossing of hDMD mice that contain the full-length 2.3 Mb hDMD gene were crossed with dystrophin-deficient mdx mice and dystrophin and utrophin double-deficient mdx x utrn-/- mice resulted in a full rescue of the dystrophic features of these mice, as concluded from histological analysis. Analysis on Affymetrix gene chips demonstrated that also expression profiles of the dystrophic mice were normalized by crossing with transgenic hDMD mice. This confirms the full functionality of the hDMD transgene in mice. Experiment Overall Design: RNA from gastrocnemius muscle from individual mice was hybridized to Affymetrix U74Av2
Project description:Duchenne muscular dystrophy (DMD) is a severely debilitating and incurable neuromuscular disease. Its conspicuous feature is the absence of dystrophin in myofibers and therefore most therapeutic approaches focus on some form of its re-expression there. However, increasing body of evidence points at an early developmental onset of DMD and severe abnormalities were uncovered in dystrophic muscle stem cells. In this study, we explore gene expression changes in primary myoblasts from mice lacking expression of the full length dystrophin transcript. Total RNA extracted from primary myoblasts isolated from gastrocnemii of 8 week old male Dmd-mdx (MDX - lacking the full length dystrophin transcript), Dmd-mdx-βgeo (BGEO - lacking all dystrophin expression) and control mice (WT) were subjected to RNA sequencing following ribodepletion, and analysed for the differential expression of genes between groups and the enrichment of gene ontology categories or pathways.
Project description:This study applies targeted Cas9-based gene insertion strategies for the correction of full-length dystrophin in a pre-clinical humanized mouse model of Duchenne muscular dystrophy. Following intramuscular or intravenous delivery, full-length dystrophin is restored in skeletal and cardiac muscle.
Project description:We created mice, which are deficient for Myc specifically in cardiac myocytes by crossing crossed Myc-floxed mice (Mycfl/fl) and MLC-2VCre/+ mice. Serial analysis of earlier stages of gestation revealed that Myc-deficient mice died prematurely at E13.5-14.5. Morphological analyses of E13.5 Myc-null embryos showed normal ventricular size and structure; however, decreased cardiac myocyte proliferation and increased apoptosis was observed. BrdU incorporation rates were also decreased significantly in Myc-null myocardium. Myc-null mice displayed a 3.67-fold increase in apoptotic cardiomyocytes by TUNEL assay. We examined global gene expression using oligonucleotide microarrays. Numerous genes involved in mitochondrial death pathways were dysregulated including Bnip3L and Birc2. Keywords: wildtype vs Myc-null
Project description:We created mice, which are deficient for Myc specifically in cardiac myocytes by crossing crossed Myc-floxed mice (Mycfl/fl) and MLC-2VCre/+ mice. Serial analysis of earlier stages of gestation revealed that Myc-deficient mice died prematurely at E13.5-14.5. Morphological analyses of E13.5 Myc-null embryos showed normal ventricular size and structure; however, decreased cardiac myocyte proliferation and increased apoptosis was observed. BrdU incorporation rates were also decreased significantly in Myc-null myocardium. Myc-null mice displayed a 3.67-fold increase in apoptotic cardiomyocytes by TUNEL assay. We examined global gene expression using oligonucleotide microarrays. Numerous genes involved in mitochondrial death pathways were dysregulated including Bnip3L and Birc2. Hearts were taken from wide type and Myc-null Mouse embryos at E13.5 under the dissecting scope. Cardiac myocyte RNA was isolated using TRIZOL®Reagent Total RNA (100 ng) was hybridized to the Sentrix® MouseRef-8 Expression BeadChip that contains probes for ~24,000 transcripts. GeneChips were scanned using the Hewlett-Packard GeneArray Scanner G2500A. The data were analyzed with Illumina Inc. BeadStudio version 1.5.0.34 and normalized by rank invariant method.
Project description:Duchenne muscular dystrophy (DMD) is a severe form of muscular dystrophy caused by mutations in the dystrophin gene. We characterized which isoforms of dystrophin were expressed by human induced pluripotent stem cell (hiPSC)-derived cardiac fibroblasts obtained from control and DMD patients. Distinct dystrophin isoforms were observed; however, the highest molecular weight isoform was absent in DMD patients carrying exon deletions or mutations in the dystrophin gene. The loss of the full-length dystrophin isoform in hiPSC-derived cardiac fibroblasts from DMD patients resulted in deficient formation of actin microfilaments and a metabolic switch from mitochondrial oxidation to glycolysis. The DMD hiPSC-derived cardiac fibroblasts exhibited a dysregulated mitochondria network and reduced mitochondrial respiration, with enhanced compensatory glycolysis to sustain cellular ATP production. This metabolic remodeling was associated with an exacerbated myofibroblast phenotype and increased fibroblast activation in response to pro fibrotic challenges. As cardiac fibrosis is a critical pathological feature of the DMD heart, the myofibroblast phenotype induced by the absence of dystophin may contribute to deterioration in cardiac function. Our study highlights therelationship between cytoskeletal dynamics, metabolism of the cell and myofibroblast differentiation and provides a new mechanism by which inactivation of dystrophin in non-cardiomyocyte cells may increase the severity of cardiopathy.
Project description:The 2.2 Mb long dystrophin (DMD) gene, the largest gene in the human genome, corresponds to roughly 0.1% of the entire human DNA sequence. Mutations in this gene cause Duchenne muscular dystrophy and other milder X-linked, recessive dystrophinopathies. Using a custom-made tiling array, specifically designed for the DMD locus, we identified a variety of novel long non-coding RNAs (ncRNAs), both sense and antisense oriented, whose expression profiles mirror that of DMD gene. Importantly, these transcripts are intronic in origin and specifically localized to the nucleus and are transcribed contextually with dystrophin isoforms or primed by MyoD-induced myogenic differentiation. Furthermore, their forced ectopic expression in both human muscle and neuronal cells causes a specific and negative regulation of endogenous dystrophin full length isoforms and significantly down-regulate the activity of a luciferase reporter construct carrying the minimal promoter regions of the muscle dystrophin isoform. Consistent with this apparently repressive role, we found that, in muscle samples of DMD symptomatic female carriers, lncRNAs expression levels inversely correlate with those of muscle full length DMD isoforms. Overall these findings unveil an unprecedented complexity of the transcriptional pattern of the DMD locus and reveal that DMD-specific lncRNAs may contribute to the orchestration and homeostasis of the muscle dystrophin expression pattern by selective targeting and down-modulation of dystrophin promoter transcriptional activity.
Project description:We tried two methods which are the DNase I treated full-length double-strand cDNA sequencing and the poly(A) capture full-length double-strand cDNA sequencing to avoid the non-specific genomic DNA amplification.