title: Establishment of a human skeletal muscle-derived cell line: biochemical, cellular and electrophysiological characterization.
abstract: Excitation-contraction coupling is the physiological mechanism occurring in muscle cells whereby an electrical signal sensed by the dihydropyridine receptor located on the transverse tubules is transformed into a chemical gradient (Ca2+ increase) by activation of the ryanodine receptor located on the sarcoplasmic reticulum membrane. In the present study, we characterized for the first time the excitation-contraction coupling machinery of an immortalized human skeletal muscle cell line. Intracellular Ca2+ measurements showed a normal response to pharmacological activation of the ryanodine receptor, whereas 3D-SIM (super-resolution structured illumination microscopy) revealed a low level of structural organization of ryanodine receptors and dihydropyridine receptors. Interestingly, the expression levels of several transcripts of proteins involved in Ca2+ homoeostasis and differentiation indicate that the cell line has a phenotype closer to that of slow-twitch than fast-twitch muscles. These results point to the potential application of such human muscle-derived cell lines to the study of neuromuscular disorders; in addition, they may serve as a platform for the development of therapeutic strategies aimed at correcting defects in Ca2+ homoeostasis due to mutations in genes involved in Ca2+ regulation.
authors.affiliation: ‡Department of Physiology, University of Bern, Bern, Switzerland.
authors.forename: Ori
authors.initials: O
authors.lastname: Rokach
authors.forename: Nina D
authors.initials: ND
authors.lastname: Ullrich
authors.forename: Martin
authors.initials: M
authors.lastname: Rausch
authors.forename: Vincent
authors.initials: V
authors.lastname: Mouly
authors.forename: Haiyan
authors.initials: H
authors.lastname: Zhou
authors.forename: Francesco
authors.initials: F
authors.lastname: Muntoni
authors.forename: Francesco
authors.initials: F
authors.lastname: Zorzato
authors.forename: Susan
authors.initials: S
authors.lastname: Treves
mesh_terms: D002118:Calcium / Q000378:metabolism*; D020746:Calcium Channels, L-Type / Q000378:metabolism; D002460:Cell Line; D055724:Electrophysiological Phenomena; D005260:Female; D006801:Humans; D009119:Muscle Contraction; D009124:Muscle Proteins / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism*; D019837:Ryanodine Receptor Calcium Release Channel / Q000378:metabolism; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D055815:Young Adult
chemical_list: D020746:Calcium Channels, L-Type; D009124:Muscle Proteins; D019837:Ryanodine Receptor Calcium Release Channel; D002118:Calcium