title: A Drosophila model of oculopharyngeal muscular dystrophy reveals intrinsic toxicity of PABPN1.
abstract: Oculopharyngeal muscular dystrophy (OPMD) is an adult-onset syndrome characterized by progressive degeneration of particular muscles. OPMD is caused by short GCG repeat expansions within the gene encoding the nuclear poly(A)-binding protein 1 (PABPN1) that extend an N-terminal polyalanine tract in the protein. Mutant PABPN1 aggregates as nuclear inclusions in OMPD patient muscles. We have created a Drosophila model of OPMD that recapitulates the features of the human disorder: progressive muscle degeneration, with muscle defects proportional to the number of alanines in the tract, and formation of PABPN1 nuclear inclusions. Strikingly, the polyalanine tract is not absolutely required for muscle degeneration, whereas another domain of PABPN1, the RNA-binding domain and its function in RNA binding are required. This demonstrates that OPMD does not result from polyalanine toxicity, but from an intrinsic property of PABPN1. We also identify several suppressors of the OPMD phenotype. This establishes our OPMD Drosophila model as a powerful in vivo test to understand the disease process and develop novel therapeutic strategies.
authors.affiliation: Génétique du Développement de la Drosophile, Institut de Génétique Humaine, CNRS UPR 1142, Montpellier Cedex 5, France.
authors.forename: Aymeric
authors.initials: A
authors.lastname: Chartier
authors.forename: Béatrice
authors.initials: B
authors.lastname: Benoit
authors.forename: Martine
authors.initials: M
authors.lastname: Simonelig
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D004195:Disease Models, Animal; D004331:Drosophila melanogaster / Q000033:anatomy & histology / Q000502:physiology*; D006801:Humans; D018832:Molecular Chaperones / Q000378:metabolism; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000378:metabolism / Q000473:pathology; D039141:Muscular Dystrophy, Oculopharyngeal / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D010641:Phenotype; D039122:Poly(A)-Binding Protein I / Q000235:genetics / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D014921:Wings, Animal / Q000033:anatomy & histology
chemical_list: D018832:Molecular Chaperones; D039122:Poly(A)-Binding Protein I; D016159:Tumor Suppressor Protein p53