Dystrophin-glycoprotein complex

Worton, R., 1995. Mnscnlar dystrophies Diseases of die dystrophin-glycoprotein complex. Science 270 755-756. 

While one end of the dystrophin molecule binds to actin filaments, the C-terminal domain associates with several additional proteins to form a dystrophin-glycoprotein complex (see figure)/1 k Dystrophin is linked directly to the membrane-spanning protein P-dystroglycan, which in the outer membrane surfaces associates with a glycoprotein a-dystroglycan. The latter binds to laminin-2 (Fig. 8-33), a protein that binds the cell to the basal lamina. Four... 

Schematic model of the dystrophin-glycoprotein complex. Courtesy of Kevin P. Campbell. See Lim and Campbell1 Abbreviations LGMD, Limb Girdle muscular dystrophy CMD, congenital muscular dystrophy DMD / BMD, Duchenne / Becker muscular dystrophies.

Ervasti, J. M., and Campbell, K. P. (1993b). A role for the dystrophin-glycoprotein complex as a transmembrane linker between laminin and actin. J. Cell Biol. 122, 809-823. 

Ran do, T. A. (2001). The dystrophin-glycoprotein complex, cellular signaling, and the regulation of cell survival in the muscular dystrophies. Muscle Nerve 24, 1575-1594. 

Keywords dystrophin-glycoprotein complex, sarcolemma, membrane tears, calcium channels,... 

Figure 1. The muscle dystrophin-glycoprotein complex. The dystrophin-glycoprotein complex normally spans the plasma membrane of the skeletal muscle cell and may stabilize the sarcolemma and cytoskeleton to allow force transduction between the intracellular cytoskeleton (F-actin filaments) and the extracellular matrix. The molecules indicated are core components of the dystrophin-glycoprotein complex. Laminin 2 is the predominant laminin isoform in skeletal muscle basement membranes. Modified from McNeil and Steinhardt (2003)...

Halayko, A.J., and Stelmack, G.L., 2005, The association of caveolae, actin, and the dystrophin-glycoprotein complex a role in smooth muscle phenotype and function , Can J Physiol Pharmacol, 83, pp 877-891. 

Rybakova, I.N., and Ervasti, J.M., 1997, Dystrophin-glycoprotein complex is monomeric and stabilizes actin filaments in vitro through a lateral association, J Biol Chem, 272, pp 28771-28778. 

Galbiati, F., Engelman, J. A., Volonte, D., Zhang, X. L., Minetti, C., Li, M., et al. (2001) Caveolin-3 null mice show a loss of caveolae, changes in the microdomain distribution of the dystrophin-glycoprotein complex, and t-tubule abnormalities. J Biol Chem 276,21425-21433. 

Yue, Y. P., Li, Z. B., Harper, S. Q. et al. (2003). Microdystrophin gene therapy of cardiomyopathy restores dystrophin-glycoprotein complex and improves sarcolemma integrity in the mdx mouse heart. Circulation 108(13), 1626-1632. 

Haenggi T, Fritschi J-M. 2006. Role of dystrophin and utro-phin for assembly and function of the dystrophin glycoprotein complex in non-muscle tissue. Cell Mol Life Sci 63 1614-1631. 

Focal adhesions (in muscle often referred to as costameres) are regions that are associated with the sarcolemma of skeletal muscle fibres and comprise proteins of the dystrophin-glycoprotein complex and vinculin-talin-integrin system. Focal adhesions play both a mechanical and a signalling role, transmitting force from the contractile apparatus to the extracellular matrix in order to stabilise skeletal-muscle fibres during contraction and relaxation. Several focal adhesion constituent proteins have been shown to be defective in muscular dystrophies and cardiomyopathies. 

Straub V, Campbell KP. Muscular dystrophies and the dystrophin-glycoprotein complex. Curr Opin Neurol 1997 10 168-75. 

Grozdanovic Z, Baumgarten HG. 1999. Nitric oxide synthase in skeletal muscle fibers A signaling component of the dystrophin-glycoprotein complex. Histol Hisotpathol 14 243-256. 

A FIGURE 6-29 Schematic model of the dystrophin glycoprotein complex (DGC) in skeletal muscle cells. The... 

Durbeej, M., and K. P. Campbell. 2002. Muscular dystrophies involving the dystrophin-glycoprotein complex an overview of current mouse models. Curr. Opin. Genet Devel. 12 349-361. 

Michele DB, Campbell KP. (2003) Dystrophin-glycoprotein complex post-translational processing and dystroglycan function. J Biol Chem 278(18), 15457-15460. 

---