Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We recently showed that cytoplasmic gamma-actin (gamma(cyto)-actin) is dramatically elevated in striated muscle of dystrophin-deficient mdx mice. Here, we demonstrate that gamma(cyto)-actin is markedly increased in golden retriever muscular dystrophy (GRMD), which better recapitulates the dystrophinopathy phenotype in humans. Gamma(cyto)-Actin was also elevated in muscle from alpha-sarcoglycan null mice, but not in several other dystrophic animal models, including mice deficient in beta-sarcoglycan, alpha-dystrobrevin, laminin-2, or alpha7 integrin. Muscle from mice lacking dystrophin and utrophin also expressed elevated gamma(cyto)-actin, which was not restored to normal by transgenic overexpression of alpha7 integrin. However, gamma(cyto)-actin was further elevated in skeletal muscle from GRMD animals treated with the glucocorticoid prednisone at doses shown to improve the dystrophic phenotype and muscle function. These data suggest that elevated gamma(cyto)-actin is part of a compensatory cytoskeletal remodeling program that may partially stabilize dystrophic muscle in some cases where the dystrophin-glycoprotein complex is compromised.
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PMID:Cytoplasmic gamma-actin expression in diverse animal models of muscular dystrophy. 1747 92

The organisation of structural proteins in muscle into highly ordered sarcomeres occurs during development, regeneration and focal repair of skeletal muscle fibers. The involvement of cytoskeletal proteins in this process has been documented, with nonmuscle gamma-actin found to play a role in sarcomere assembly during muscle differentiation and also shown to be up-regulated in dystrophic muscles which undergo regeneration and repair [Lloyd et al.,2004; Hanft et al.,2006]. Here, we show that a cytoskeletal tropomyosin (Tm), Tm4, defines actin filaments in two novel compartments in muscle fibers: a Z-line associated cytoskeleton (Z-LAC), similar to a structure we have reported previously [Kee et al.,2004], and longitudinal filaments that are orientated parallel to the sarcomeric apparatus, present during myofiber growth and repair/regeneration. Tm4 is upregulated in paradigms of muscle repair including induced regeneration and focal repair and in muscle diseases with repair/regeneration features, muscular dystrophy and nemaline myopathy. Longitudinal Tm4-defined filaments also are present in diseased muscle. Transition of the Tm4-defined filaments from a longitudinal to a Z-LAC orientation is observed during the course of muscle regeneration. This Tm4-defined cytoskeleton is a marker of growth and repair/regeneration in response to injury, disease state and stress in skeletal muscle.
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PMID:Tropomyosin 4 defines novel filaments in skeletal muscle associated with muscle remodelling/regeneration in normal and diseased muscle. 1796 84