Article

Muscle intermediate filaments and their links to membranes and membranous organelles. Exp Cell Res

Cell Biology Division, Center of Basic Research, Biomedical Research Foundation Academy of Athens, Soranou Efessiou 4, 12965 Athens, Greece.
Experimental Cell Research (Impact Factor: 3.25). 07/2007; 313(10):2063-76. DOI: 10.1016/j.yexcr.2007.03.033
Source: PubMed

ABSTRACT

Intermediate filaments (IFs) play a key role in the integration of structure and function of striated muscle, primarily by mediating mechanochemical links between the contractile apparatus and mitochondria, myonuclei, the sarcolemma and potentially the vesicle trafficking apparatus. Linkage of all these membranous structures to the contractile apparatus, mainly through the Z-disks, supports the integration and coordination of growth and energy demands of the working myocyte, not only with force transmission, but also with de novo gene expression, energy production and efficient protein and lipid trafficking and targeting. Desmin, the most abundant and intensively studied muscle intermediate filament protein, is linked to proper costamere organization, myoblast and stem cell fusion and differentiation, nuclear shape and positioning, as well as mitochondrial shape, structure, positioning and function. Similar links have been established for lysosomes and lysosome-related organelles, consistent with the presence of widespread links between IFs and membranous structures and the regulation of their fusion, morphology and stabilization necessary for cell survival.

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Available from: Robert J Bloch, Feb 26, 2015
    • "These proteins play an important role in sarcomeric movements by linking the contractile apparatus to the sarcolemma and extracellular matrix (ECM). The cytoskeleton also has important roles in cell shape, signal transduction, growth, division and differentiation , as well as in the movement of organelles within the cell (Capetanaki et al. 2007). In skeletal muscles the major elements of the cytoskeleton are the intermediate filaments (IFs; Paulin & Li, 2004). "
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    • "AGEs and lipid peroxidation end-products accumulate in PAD muscle and, particularly, in PAD myofibers (Norgren et al. 2007; Pipinos et al. 2008, 2007). Desmin links neighboring myofibrils into bundles through their Z-discs (Capetanaki et al. 2007; Dalakas et al. 2000), aligns the Z-discs of neighboring myofibers (Capetanaki et al. 1997; Carlsson and Thornell 2001; Lazarides 1980), organizes the mitochondria into a welldefined functional network around the myofibrils (Capetanaki et al. 1997; Milner et al. 2000) and facilitates transmission of the force of sarcomere contraction to the ECM (Bloch and Gonzalez-Serratos 2003; Capetanaki et al. 2007; Carlsson and Thornell 2001; Goldfarb et al. 2004; Paulin et al. 2004). Mitochondrial dysfunction in PAD skeletal muscle is well documented (Makris et al. 2007; Pipinos et al. 2006; Pipinos et al. 2003; Pipinos et al. 2000). "
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    • "Based on reported physical interactions in the literature and protein-protein interaction databases (BioGRID, MINT, GeneMANIA; Mostafavi et al. 2008; Stark et al. 2006), we established an interaction network for desmin (Fig. 2b). Desmin interactors include other members of the IF family, cytolinkers bridging organelles and cytoskeleton, chaperones and adaptor proteins and proteins that have been implicated in proteolysis, posttranslational modifications and signaling important for proper skeletal or cardiac muscle functions (Capetanaki et al. 2007; Costa et al. 2004). The architectural role of desmin filaments has been enriched by these new findings suggesting that desmin serves as a platform for signaling events perturbed upon desmin misfolding/ aggregation under pathological conditions. "
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