Open Access

Several dystrophin-glycoprotein complex members are present in crude surface membranes but they are sodium dodecyl sulphate invisible in KCl-washed microsomes from mdx mouse muscle

  • Stéphanie Daval1,
  • Chantal Rocher2,
  • Yan Cherel1 and
  • Elisabeth Le Rumeur2Email author
Cellular & Molecular Biology LettersAn International Journal200915:134

https://doi.org/10.2478/s11658-009-0039-8

Received: 1 April 2009

Accepted: 27 November 2009

Published: 7 December 2009

Abstract

The dystrophin-glycoprotein complex (DGC) is a large trans-sarcolemmal complex that provides a linkage between the subsarcolemmal cytoskeleton and the extracellular matrix. In skeletal muscle, it consists of the dystroglycan, sarcoglycan and cytoplasmic complexes, with dystrophin forming the core protein. The DGC has been described as being absent or greatly reduced in dystrophin-deficient muscles, and this lack is considered to be involved in the dystrophic phenotype. Such a decrease in the DGC content was observed in dystrophin-deficient muscle from humans with muscular dystrophy and in mice with X-linked muscular dystrophy (mdx mice). These deficits were observed in total muscle homogenates and in partially membrane-purified muscle fractions, the so-called KCl-washed microsomes. Here, we report that most of the proteins of the DGC are actually present at normal levels in the mdx mouse muscle plasma membrane. The proteins are detected in dystrophic animal muscles when the immunoblot assay is performed with crude surface membrane fractions instead of the usually employed KCl-washed microsomes. We propose that these proteins form SDS-insoluble membrane complexes when dystrophin is absent.

Key words

DystrophinMuscular dystrophyDystrophin-glycoprotein complex mdx miceSDS insoluble

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