The Dystrophin Complex Forms a Mechanically Strong Link between the Sarcolemma and Costameric Actin

The absence of dystrophin complex leads to disorganization of the force-transmitting costameric cytoskeleton and disruption of sarcolemmal membrane integrity in skeletal muscle. However, it has not been determined whether the dystrophin complex can form a mechanically strong bond with any costameric protein. We performed confocal immunofluorescence analysis of isolated sarcolemma that were mechanically peeled from skeletal fibers of mouse hindlimb muscle. A population of γ-actin filaments was stably associated with sarcolemma isolated from normal muscle and displayed a costameric pattern that precisely overlapped with dystrophin. However, costameric actin was absent from all sarcolemma isolated from dystrophin-deficient mdx mouse muscle even though it was localized to costameres in situ. Vinculin, α-actinin, β-dystroglycan and utrophin were all retained on mdx sarcolemma, indicating that the loss of costameric actin was not due to generalized membrane instability. Our data demonstrate that the dystrophin complex forms a mechanically strong link between the sarcolemma and the costameric cytoskeleton through interaction with γ-actin filaments. Destabilization of costameric actin filaments may also be an important precursor to the costamere disarray observed in dystrophin-deficient muscle. Finally, these methods will be broadly useful in assessing the mechanical integrity of the membrane cytoskeleton in dystrophic animal models lacking other costameric proteins.

[1]  G. Porter,et al.  Dystrophin Colocalizes with-Spectrin in Distinct Subsarcolemmal Domains in Mammalian Skeletal Muscle , 2002 .

[2]  J. Ervasti,et al.  Utrophin Lacks the Rod Domain Actin Binding Activity of Dystrophin* , 1999, The Journal of Biological Chemistry.

[3]  S. Carbonetto,et al.  Chimaeric mice deficient in dystroglycans develop muscular dystrophy and have disrupted myoneural synapses , 1999, Nature Genetics.

[4]  S. Wasiak,et al.  Dystonin-deficient mice exhibit an intrinsic muscle weakness and an instability of skeletal muscle cytoarchitecture. , 1999, Developmental biology.

[5]  R. Bloch,et al.  Extensive but Coordinated Reorganization of the Membrane Skeleton in Myofibers of Dystrophic (mdx) Mice , 1999, The Journal of cell biology.

[6]  I. Nonaka,et al.  α1-Syntrophin Gene Disruption Results in the Absence of Neuronal-type Nitric-oxide Synthase at the Sarcolemma but Does Not Induce Muscle Degeneration* , 1999, The Journal of Biological Chemistry.

[7]  H. Klamut,et al.  Identification of a novel actin binding site within the Dp71 dystrophin isoform , 1998, FEBS letters.

[8]  Nicolas Deconinck,et al.  Expression of full-length utrophin prevents muscular dystrophy in mdx mice , 1998, Nature Medicine.

[9]  J. Ervasti,et al.  A Cluster of Basic Repeats in the Dystrophin Rod Domain Binds F-actin through an Electrostatic Interaction* , 1998, The Journal of Biological Chemistry.

[10]  John A. Faulkner,et al.  Progressive Muscular Dystrophy in α-Sarcoglycan–deficient Mice , 1998, The Journal of cell biology.

[11]  M. Shigekawa,et al.  α1‐Syntrophin has distinct binding sites for actin and calmodulin , 1998, FEBS letters.

[12]  H. Lassmann,et al.  Targeted inactivation of plectin reveals essential function in maintaining the integrity of skin, muscle, and heart cytoarchitecture. , 1997, Genes & development.

[13]  J. Ervasti,et al.  Dystrophin-Glycoprotein Complex Is Monomeric and Stabilizes Actin Filaments in Vitro through a Lateral Association* , 1997, The Journal of Biological Chemistry.

[14]  K. Campbell,et al.  Animal Models for Muscular Dystrophy Show Different Patterns of Sarcolemmal Disruption , 1997, The Journal of cell biology.

[15]  T. Voit,et al.  Spatial distribution of β-spectrin in normal and dystrophic human skeletal muscle , 1997, Acta Neuropathologica.

[16]  K. Campbell,et al.  Muscular dystrophies and the dystrophin-glycoprotein complex. , 1997, Current opinion in neurology.

[17]  J. Chamberlain,et al.  Interactions between dystrophin and the sarcolemma membrane. , 1997, Society of General Physiologists series.

[18]  J. Ervasti,et al.  A new model for the interaction of dystrophin with F-actin , 1996, The Journal of cell biology.

[19]  Y. Capetanaki,et al.  Disruption of muscle architecture and myocardial degeneration in mice lacking desmin , 1996, The Journal of cell biology.

[20]  K. Campbell.  Three muscular dystrophies: Loss of cytoskeleton-extracellular matrix linkage , 1995, Cell.

[21]  C. Minetti,et al.  Abnormalities in the expression of β‐spectrin in Duchenne muscular dystrophy , 1994, Neurology.

[22]  J. Ervasti,et al.  A role for the dystrophin-glycoprotein complex as a transmembrane linker between laminin and actin , 1993, The Journal of cell biology.

[23]  H. Sweeney,et al.  Dystrophin protects the sarcolemma from stresses developed during muscle contraction. , 1993, Proceedings of the National Academy of Sciences of the United States of America.

[24]  J. Léger,et al.  Direct visualization of the dystrophin network on skeletal muscle fiber membrane , 1992, The Journal of cell biology.

[25]  J. Sanger,et al.  Costameres are sites of force transmission to the substratum in adult rat cardiomyocytes , 1992, The Journal of cell biology.

[26]  C. Minetti,et al.  Immunologic study of vinculin in Duchenne muscular dystrophy , 1992, Neurology.

[27]  G. Porter,et al.  Dystrophin Colocalizes with -spectrin in Distinct Subsarcolemmal Domains in Mammalian Skeletal Muscle , 1992 .

[28]  K. Campbell,et al.  Dystrophin-associated proteins are greatly reduced in skeletal muscle from mdx mice , 1991, The Journal of cell biology.

[29]  J. Ervasti,et al.  Membrane organization of the dystrophin-glycoprotein complex , 1991, Cell.

[30]  J. Ervasti,et al.  Dystrophin-related protein is localized to neuromuscular junctions of adult skeletal muscle , 1991, Neuron.

[31]  J. Ervasti,et al.  Deficiency of a glycoprotein component of the dystrophin complex in dystrophic muscle , 1990, Nature.

[32]  C. Otey,et al.  Immunolocalization of muscle and nonmuscle isoforms of actin in myogenic cells and adult skeletal muscle. , 1988, Cell motility and the cytoskeleton.

[33]  J. Lessard.  Two monoclonal antibodies to actin: one muscle selective and one generally reactive. , 1988, Cell motility and the cytoskeleton.

[34]  M. Pittenger,et al.  Subcellular sorting of isoactins: Selective association of γ actin with skeletal muscle mitochondria , 1983, Cell.

[35]  J. Siliciano,et al.  A vinculin-containing cortical lattice in skeletal muscle: transverse lattice elements ("costameres") mark sites of attachment between myofibrils and sarcolemma. , 1983, Proceedings of the National Academy of Sciences of the United States of America.

[36]  S. Craig,et al.  Gamma actin, spectrin, and intermediate filament proteins colocalize with vinculin at costameres, myofibril-to-sarcolemma attachment sites. , 1983, Cell motility.