Muscular dystrophy associated with alpha-dystroglycan deficiency in Sphynx and Devon Rex cats

Neuromuscul Disord. 2008 Dec;18(12):942-52. doi: 10.1016/j.nmd.2008.08.002. Epub 2008 Nov 5.

Abstract

Recent studies have identified a number of forms of muscular dystrophy, termed dystroglycanopathies, which are associated with loss of natively glycosylated alpha-dystroglycan. Here we identify a new animal model for this class of disorders in Sphynx and Devon Rex cats. Affected cats displayed a slowly progressive myopathy with clinical and histologic hallmarks of muscular dystrophy including skeletal muscle weakness with no involvement of peripheral nerves or CNS. Skeletal muscles had myopathic features and reduced expression of alpha-dystroglycan, while beta-dystroglycan, sarcoglycans, and dystrophin were expressed at normal levels. In the Sphynx cat, analysis of laminin and lectin binding capacity demonstrated no loss in overall glycosylation or ligand binding for the alpha-dystroglycan protein, only a loss of protein expression. A reduction in laminin-alpha2 expression in the basal lamina surrounding skeletal myofibers was also observed. Sequence analysis of translated regions of the feline dystroglycan gene (DAG1) in affected cats did not identify a causative mutation, and levels of DAG1 mRNA determined by real-time QRT-PCR did not differ significantly from normal controls. Reduction in the levels of glycosylated alpha-dystroglycan by immunoblot was also identified in an affected Devon Rex cat. These data suggest that muscular dystrophy in Sphynx and Devon Rex cats results from a deficiency in alpha-dystroglycan protein expression, and as such may represent a new type of dystroglycanopathy where expression, but not glycosylation, is affected.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biopsy
  • Cats
  • Disease Models, Animal
  • Dystroglycans / deficiency*
  • Dystroglycans / genetics
  • Dystroglycans / metabolism
  • Female
  • Fluorescent Antibody Technique
  • Glycosylation
  • Immunoblotting
  • Laminin / metabolism
  • Lectins / metabolism
  • Male
  • Muscle Weakness / metabolism
  • Muscle Weakness / pathology
  • Muscle, Skeletal / metabolism
  • Muscle, Skeletal / pathology*
  • Muscular Dystrophy, Animal / genetics
  • Muscular Dystrophy, Animal / metabolism
  • Muscular Dystrophy, Animal / pathology*
  • Polymerase Chain Reaction

Substances

  • DAG1 protein, human
  • Laminin
  • Lectins
  • Dystroglycans