Available at: http://hdl.handle.net/2078.1/9310 [Downloaded 2024/04/15 at 07:13:28 ] "New aspects of calcium signaling in skeletal muscle cells: implications in Duchenne muscular dystrophy." Gailly, Philippe ABSTRACT Calcium is the most ubiquitous second messenger. Its concentration inside the cell is tightly regulated by a series of mechanisms, among which some have been extensively studied in nonmuscle cells. This is the case of the "store-operated entry of Ca(2+)", the uptake of Ca(2+) by mitochondria and the inositol 1,4,5-trisphosphate (IP(3)) cascade. These processes were recently found to be also present in skeletal muscle and are reviewed here. The "store-operated entry of Ca(2+)" allows the refilling of the stores after muscle fiber depolarization and is activated even after a partial depletion of the sarcoplasmic reticulum (SR). The uptake of Ca(2+) by mitochondria accelerates muscle relaxation and allows the adaptation of ATP supply to the increased energy demand. IP(3) receptors are found in the nuclear envelope and are involved in Ca(2+) waves propagating from one nucleus to another. This pathway is possibly involved in gene expression regulation. Finally, cytosolic Ca(2+) buffers like parvalbumins modify [Ca(2+)](i) transients and, therefore, muscle mechanics.The importance of these regulation mechanisms is also evaluated in Duchenne muscular dystrophy (DMD), a disease in which impairment of [Ca(2+)](i) homeostasis has been postulated but remains, however, controversial. This genetic disease is indeed characterized by the absence of a cytoskeletal protein called dystrophin, a situation leading to a disorganization of the cytoskeleton and to an abnormal influx of Ca(2+). How this increased entry of Ca(2+) affects the local concentration of Ca(2+) in subcellular compartmen... CITE THIS VERSION Gailly, Philippe. New aspects of calcium signaling in skeletal muscle cells: implications in Duchenne muscular dystrophy.. In: Biochimica et biophysica acta, Vol. 1600, no. 1-2, p. 38-44 (2002) http:// hdl.handle.net/2078.1/9310 Le dépôt institutionnel DIAL est destiné au dépôt et à la diffusion de documents scientifiques émanant des membres de l'UCLouvain. Toute utilisation de ce document à des fins lucratives ou commerciales est strictement interdite. L'utilisateur s'engage à respecter les droits d'auteur liés à ce document, principalement le droit à l'intégrité de l'œuvre et le droit à la paternité. La politique complète de copyright est disponible sur la page Copyright policy DIAL is an institutional repository for the deposit and dissemination of scientific documents from UCLouvain members. Usage of this document for profit or commercial purposes is stricly prohibited. User agrees to respect copyright about this document, mainly text integrity and source mention. Full content of copyright policy is available at Copyright policy