The Dystroglycan Complex stabilizes attachments of Muscle Cells to the ECM

The Costamere is an attachment structure at the surface of striated muscle which links the actomyosin cytoskeleton to the ECM and is important for maintenance of muscle integrity. Costameres contain many of the same proteins found at focal adhesion sites in addition to the protein Dystrophin, a very large skeletal muscle protein which makes up 5% of membrane-associated cytoskeleton in skeletal muscle cells. Dystrophin links cortical cytoskeleton actin filaments to the extracellular matrix (ECM) via Laminin and a transmembrane glycoprotein, called the Dystroglycan complex.