| 1. |
- Fugier, Charlotte, et al.
(författare)
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Misregulated alternative splicing of BIN1 is associated with T tubule alterations and muscle weakness in myotonic dystrophy
- 2011
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Ingår i: Nature medicine. - : Springer Science and Business Media LLC. - 1546-170X .- 1078-8956. ; 17:6, s. 720-725
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Tidskriftsartikel (refereegranskat)abstract
- Myotonic dystrophy is the most common muscular dystrophy in adults and the first recognized example of an RNA-mediated disease. Congenital myotonic dystrophy (CDM1) and myotonic dystrophy of type 1 (DM1) or of type 2 (DM2) are caused by the expression of mutant RNAs containing expanded CUG or CCUG repeats, respectively. These mutant RNAs sequester the splicing regulator Muscleblind-like-1 (MBNL1), resulting in specific misregulation of the alternative splicing of other pre-mRNAs. We found that alternative splicing of the bridging integrator-1 (BIN1) pre-mRNA is altered in skeletal muscle samples of people with CDM1, DM1 and DM2. BIN1 is involved in tubular invaginations of membranes and is required for the biogenesis of muscle T tubules, which are specialized skeletal muscle membrane structures essential for excitation-contraction coupling. Mutations in the BIN1 gene cause centronuclear myopathy, which shares some histopathological features with myotonic dystrophy. We found that MBNL1 binds the BIN1 pre-mRNA and regulates its alternative splicing. BIN1 missplicing results in expression of an inactive form of BIN1 lacking phosphatidylinositol 5-phosphate-binding and membrane-tubulating activities. Consistent with a defect of BIN1, muscle T tubules are altered in people with myotonic dystrophy, and membrane structures are restored upon expression of the normal splicing form of BIN1 in muscle cells of such individuals. Finally, reproducing BIN1 splicing alteration in mice is sufficient to promote T tubule alterations and muscle weakness, a predominant feature of myotonic dystrophy.
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| 2. |
- Ageron, M., et al.
(författare)
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ANTARES : The first undersea neutrino telescope
- 2011
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 656:1, s. 11-38
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Tidskriftsartikel (refereegranskat)abstract
- The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given. (C) 2011 Elsevier B.V. All rights reserved.
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| 3. |
- Joanne, Pierre, et al.
(författare)
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Impaired Adaptive Response to Mechanical Overloading in Dystrophic Skeletal Muscle
- 2012
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 7:4, s. e35346-
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Tidskriftsartikel (refereegranskat)abstract
- Dystrophin contributes to force transmission and has a protein-scaffolding role for a variety of signaling complexes in skeletal muscle. In the present study, we tested the hypothesis that the muscle adaptive response following mechanical overloading (ML) would be decreased in MDX dystrophic muscle lacking dystrophin. We found that the gains in muscle maximal force production and fatigue resistance in response to ML were both reduced in MDX mice as compared to healthy mice. MDX muscle also exhibited decreased cellular and molecular muscle remodeling (hypertrophy and promotion of slower/oxidative fiber type) in response to ML, and altered intracellular signalings involved in muscle growth and maintenance (mTOR, myostatin, follistatin, AMPK alpha 1, REDD1, atrogin-1, Bnip3). Moreover, dystrophin rescue via exon skipping restored the adaptive response to ML. Therefore our results demonstrate that the adaptive response in response to ML is impaired in dystrophic MDX muscle, most likely because of the dystrophin crucial role.
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| 4. |
- Mounier, Remi, et al.
(författare)
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AMPK alpha 1 Regulates Macrophage Skewing at the Time of Resolution of Inflammation during Skeletal Muscle Regeneration
- 2013
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Ingår i: Cell Metabolism. - : Elsevier BV. - 1550-4131. ; 18:2, s. 251-264
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Tidskriftsartikel (refereegranskat)abstract
- Macrophages control the resolution of inflammation through the transition from a proinflammatory (M1) to an anti-inflammatory (M2) phenotype. Here, we present evidence for a role of AMPK alpha 1, a master regulator of energy homeostasis, in macrophage skewing that occurs during skeletal muscle regeneration. Muscle regeneration was impaired in AMPK alpha 1(-/-) mice. In vivo loss-of-function (LysM-Cre;AMPK alpha 1(fl/fl) mouse) and rescue (bone marrow transplantation) experiments showed that macrophagic AMPK alpha 1 was required for muscle regeneration. Cell-based experiments revealed that AMPK alpha 1(-/-) macrophages did not fully acquire the phenotype or the functions of M2 cells. In vivo, AMPK alpha 1(-/-) leukocytes did not acquire the expression of M2 markers during muscle regeneration. Skewing from M1 toward M2 phenotype upon phagocytosis of necrotic and apoptotic cells was impaired in AMPK alpha 1(-/-) macrophages and when AMPK activation was prevented by the inhibition of its upstream activator, CaMKK beta. In conclusion, AMPK alpha 1 is crucial for phagocytosis-induced macrophage skewing from a pro-to anti-inflammatory phenotype at the time of resolution of inflammation.
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