β-Dystroglycan can be revealed in microsomes from mdx mouse muscle by detergent treatment

β-Dystroglycan is the central member of a transmembrane protein complex of the skeletal muscle plasma membrane. Since it was not detected in dystrophin-deficient skeletal muscles, a disruption of the complex was thought to be involved in the dystrophic process. We report here that β-dystroglycan is actually present at normal levels in mdx mouse muscle plasma membrane: treatment with cholate detergent is able to reveal its presence by SDS–PAGE and immunoblotting. This result shows that, in dystrophin-deficient muscles, β-dystroglycan is indeed targeted to the plasma membrane but remains inaccessible to classical solubilizing treatments and to antibodies used for immunolocalization.