alpha-Dystroglycan does not play a major pathogenic role in autosomal recessive hereditary inclusion-body myopathy

Neuromuscul Disord. 2005 Feb;15(2):177-84. doi: 10.1016/j.nmd.2004.10.001. Epub 2004 Dec 10.

Abstract

Mutations of the GNE gene are responsible for autosomal recessive hereditary inclusion-body myopathy (HIBM). In this study we searched for the presence of any significant abnormality of alpha-dystroglycan (alpha-DG), a highly glycosylated component of the dystrophin-glycoprotein complex, in 5 HIBM patients which were previously clinically and genetically characterized. Immunocytochemical and immunoblot analysis showed that alpha-DG extracted from muscle biopsies was normally expressed and displayed its typical molecular mass. Immunoblot analysis on the wheat germ lectin-enriched glycoprotein fraction of muscles and primary myotubes showed a reduced amount of alpha-DG in 4 out of 5 HIBM patients, compared to normal and other diseased muscles. However, such altered lectin-binding behaviour, possibly reflecting a partial hyposialylation of alpha-DG, did not affect the laminin binding properties of alpha-DG. Therefore, the subtle changes within the alpha-DG glycosylation pattern, detected in HIBM muscles, likely do not play a key pathogenic role in this disorder.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Chromosome Disorders / genetics
  • Chromosome Disorders / metabolism*
  • Down-Regulation / physiology
  • Dystroglycans / genetics
  • Dystroglycans / metabolism*
  • Female
  • Genes, Recessive / genetics*
  • Genetic Predisposition to Disease
  • Glycosylation
  • Humans
  • Immunohistochemistry
  • Laminin / metabolism
  • Male
  • Middle Aged
  • Muscle Fibers, Skeletal / metabolism
  • Muscle Fibers, Skeletal / pathology
  • Muscle, Skeletal / metabolism*
  • Muscle, Skeletal / pathology
  • Muscle, Skeletal / physiopathology
  • Myositis, Inclusion Body / congenital*
  • Myositis, Inclusion Body / genetics
  • Myositis, Inclusion Body / metabolism*
  • Protein Binding / physiology

Substances

  • Laminin
  • Dystroglycans