Project description:Dysferlin is expressed in skeletal and cardiac muscle. However, dysferlin deficiency, namely limb girdle muscular dystrophy 2B (LGMD2B) and Myoshi myopathy, results in skeletal muscle weakness and spares the heart. This dichotomy could be caused by differential regulation of protective mechanisms. Therefore, we compared intraindividual mRNA expression profiles between cardiac and skeletal muscle in dysferlin-deficient SJL/J mice and normal C57BL/6 mice. Keywords: parallel sample
Project description:Dysferlin is expressed in skeletal and cardiac muscle. However, dysferlin deficiency, namely limb girdle muscular dystrophy 2B (LGMD2B) and Myoshi myopathy, results in skeletal muscle weakness and spares the heart. This dichotomy could be caused by differential regulation of protective mechanisms. Therefore, we compared intraindividual mRNA expression profiles between cardiac and skeletal muscle in dysferlin-deficient SJL/J mice and normal C57BL/6 mice. Experiment Overall Design: 20 chips were analyzed. They represent 4 groups of 5 replicates each. Experiment Overall Design: The 4 groups are cardiac (LV) and skeletal muscle of normal and dysferlin deficient mice. Experiment Overall Design: Tissues from normal mice are the controls in comparison to tissues of dysferlin deficient mice.
Project description:We have performed expression profiling to define the molecular changes in dysferlinopathy using a novel dedicated microarray platform made with 3’-end skeletal muscle cDNAs. Eight dysferlinopathy patients, defined by western blot, immunohistochemistry and mutation analysis, were investigated with this technology. The expression profiles of patients with different clinical traits were independently obtained and hierarchical clustering was applied to discover patient-specific gene variations. MHC class I genes and genes involved in protein biosynthesis were up-regulated in relation to muscle histopathological features. Conversely, the expression of genes codifying the sarcomeric proteins titin, nebulin and telethonin was down-regulated. Neither calpain-3 nor caveolin, a sarcolemmal protein interacting with dysferlin, was consistently reduced. There was a major up-regulation of proteins interacting with calcium, namely S100 calcium-binding proteins and sarcolipin, a sarcoplasmic calcium regulator. Keywords: Dysferlinopathies, limb-girdle muscular dystrophy type 2B,biopsy, cDNA microarray
Project description:Comparative analysis of gene expression levels from hindlimb muscle tissue from 8 week old mouse models for muscular dystrophy. We have used mouse models with dystrophin-, sarcoglycan-, sarcospan-, or dysferlin-deficiency. Keywords = muscular dystrophy Keywords: other
Project description:Comparative analysis of gene expression levels from hindlimb muscle tissue from 8 week old mouse models for muscular dystrophy. We have used mouse models with dystrophin-, sarcoglycan-, sarcospan-, or dysferlin-deficiency. Keywords = muscular dystrophy
Project description:Galectin-1 is being used as potential therapeutic to alleviate the progression onset of pathologies exhibited in Limb Girdle Muscular Dystrophy Type 2B.
Project description:Dysferlin is an essential muscle membrane repair protein and autosomal recessive mutations in its gene result in progressive muscular dystrophies collectively called dysferlinopathies. We previously showed that calpain-mediated cleavage within dysferlin exon 40a releases a 72kDa C-terminal minidysferlin recruited to injured sarcolemma. In the current study, we hypothesised that knocking out exon 40a will lead to defective membrane repair and development of muscular dystrophy over time. To address this hypothesis, we created three exon 40a knockout (40aKO) mouse lines with dysferlin protein levels ranging from ~80% of wildtype (WT) in 40aKO-3, ~50% in 40aKO-2 and ~10-20% in 40aKO-1 mice. Histopathological analysis of skeletal muscles harvested from all 12-month-old 40aKO mice showed little evidence of dystrophic features seen in dysferlin-null BLAJ mice. Lipidomics analysis on 18wk old quadriceps showed that all 40aKO lines had a similar lipidomic profile to WT and distinct from BLAJs. The proteomic profile of 40aKO lines was intermediate between that of WT and BLAJs. Laser membrane damage assays showed normal membrane repair capacity in all three 40aKO lines. These results collectively indicate that ~10-20% of dysferlin protein expression is sufficient for maintenance of the lipidome and membrane repair capacity, and crucially prevents development of muscular dystrophy.
Project description:Dysferlin is an essential muscle membrane repair protein and autosomal recessive mutations in its gene result in progressive muscular dystrophies collectively called dysferlinopathies. We previously showed that calpain-mediated cleavage within dysferlin exon 40a releases a 72kDa C-terminal minidysferlin recruited to injured sarcolemma. In the current study, we hypothesised that knocking out exon 40a will lead to defective membrane repair and development of muscular dystrophy over time. To address this hypothesis, we created three exon 40a knockout (40aKO) mouse lines with dysferlin protein levels ranging from ~80% of wildtype (WT) in 40aKO-3, ~50% in 40aKO-2 and ~10-20% in 40aKO-1 mice. Histopathological analysis of skeletal muscles harvested from all 12-month-old 40aKO mice showed little evidence of dystrophic features seen in dysferlin-null BLAJ mice. Lipidomics analysis on 18wk old quadriceps showed that all 40aKO lines had a similar lipidomic profile to WT and distinct from BLAJs. The proteomic profile of 40aKO lines was intermediate between that of WT and BLAJs. Laser membrane damage assays showed normal membrane repair capacity in all three 40aKO lines. These results collectively indicate that ~10-20% of dysferlin protein expression is sufficient for maintenance of the lipidome and membrane repair capacity, and crucially prevents development of muscular dystrophy.