title: Characterization of WWP1 protein expression in skeletal muscle of muscular dystrophy chickens.
abstract: A missense mutation in the gene encoding WWP1 was identified as the most promising candidate responsible for chicken muscular dystrophy (MD) by genetic linkage analysis. WWP1 is a HECT-type E3 ubiquitin protein ligase composed of 922 amino acids, which contains 4 tandem WW domains that interact with the proline-rich peptide motifs of target proteins. The missense mutation changes arginine 441 that is located in the centre of the WW domains into glutamine (R441Q), which potentially affects the function of the WWP1 protein. Here, we show that WWP1 is detected as ∼130-kDa protein that localizes to various structures, such as the plasma membrane (sarcolemma), sarcoplasmic reticulum, mitochondria and nucleus, in normal chicken skeletal muscle. However, in MD chickens, the mutant WWP1 protein was markedly degraded and was absent in the sarcolemma. These changes were also observed in the muscles of chickens in early pre-pathological states. Moreover, in vitro expression analysis showed significant degradation of mutant, but not wild-type WWP1, specifically in myogenic cells. Altogether, our data revealed that the R441Q missense mutation in the WWP1 protein causes degradation and loss of the sarcolemmal localization of WWP1, which may play a role in the pathogenesis of chicken MD.
authors: Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi-cho, Kodaira, Tokyo 187-8502, Japan; imamura@ncnp.go.jp.
authors: Michihiro
authors: M
authors: Imamura
authors: Intractable Disease Care Center, Shinshu University Hospital, 3-1-1 Asahi, Matsumoto 390-8621, Japan; and.
authors: Akinori
authors: A
authors: Nakamura
authors: Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Nada, Kobe 657-8501, Japan.
authors: Hideyuki
authors: H
authors: Mannen
authors: Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi-cho, Kodaira, Tokyo 187-8502, Japan;
authors: Shin'ichi
authors: S
authors: Takeda
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D002645:Chickens / Q000235:genetics / Q000378:metabolism*; D007150:Immunohistochemistry; D008928:Mitochondria / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology; D009137:Muscular Dystrophy, Animal / Q000235:genetics / Q000378:metabolism*; D020125:Mutation, Missense; D011201:Poultry Diseases / Q000235:genetics / Q000378:metabolism*; D059748:Proteolysis; D012508:Sarcolemma / Q000378:metabolism; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: D044767:Ubiquitin-Protein Ligases
keywords: E3 ubiquitin ligase; WWP1; muscular dystrophy; protein degradation; sarcolemma