Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
The formation of acetylcholine receptor (AChR) clusters can be experimentally induced in cultured Xenopus myotomal muscle cells by positive polypeptide-coated latex beads (Peng, H.B., P.-C. Cheng, and P.W. Luther, 1981, Nature [Lond.], 292:831-834). This provides a simple procedure for studying the cellular process of AChR clustering. In this study, the involvement of calcium and calmodulin in this process was examined. A deprivation in extracellular calcium by calcium-free medium or by the addition of calcium antagonists such as divalent cations Co2+ and Ni2+ (1-5 mM) or organic compounds verapamil and D-600 (0.1-0.5 mM) suppressed the formation of AChR clusters induced by the latex beads in a largely reversible manner. Antagonists against calmodulin, including trifluoperazine (1-5 microM) and the naphthalene sulfonamide W-7 (20 microM), also suppressed AChR clustering. However, the effect of W-7 was much weaker than that of trifluoperazine (TFP). Although the formation of AChR clusters is inhibited by these drugs, the stability of the existent clusters is relatively insensitive to them. These data suggest that the clustering of AChR involves a Ca2+ and calmodulin-activated process. Immunofluorescence studies using an antibody against calmodulin indicate that calmodulin is diffusely distributed in the cytoplasm in addition to its localization at the I-bands. Thus I propose that a local rise in intracellular calcium caused by a locally applied stimulus, exemplified here by the polypeptide-coated latex beads, may trigger the formation of AChR clusters. Furthermore, the cellular machinery for this process may involve calmodulin and is diffusely distributed in the muscle cell.
Almers,
Slow calcium and potassium currents across frog muscle membrane: measurements with a vaseline-gap technique.
1981, Pubmed
Almers,
Slow calcium and potassium currents across frog muscle membrane: measurements with a vaseline-gap technique.
1981,
Pubmed Anderson,
Effects of innervation on the distribution of acetylcholine receptors on cultured muscle cells.
1977,
Pubmed
,
Xenbase Anderson,
Nerve-induced and spontaneous redistribution of acetylcholine receptors on cultured muscle cells.
1977,
Pubmed
,
Xenbase Bloch,
Dispersal and reformation of acetylcholine receptor clusters of cultured rat myotubes treated with inhibitors of energy metabolism.
1979,
Pubmed Brehm,
Metabolism of acetylcholine receptors on embryonic amphibian muscle.
1983,
Pubmed
,
Xenbase Cheung,
Calmodulin plays a pivotal role in cellular regulation.
1980,
Pubmed Cohen,
Localization of acetylcholine receptors and synaptic ultrastructure at nerve-muscle contacts in culture: dependence on nerve type.
1980,
Pubmed
,
Xenbase Douglas,
On the calcium receptor activating exocytosis: inhibitory effects of calmodulin-interacting drugs on rat mast cells.
1982,
Pubmed Eisenberg,
Paralysis of frog skeletal muscle fibres by the calcium antagonist D-600.
1983,
Pubmed Fambrough,
Trophic functions of the neuron. I. Development of neural connections. Receptor properties of developing muscle.
1974,
Pubmed Fleckenstein,
Specific pharmacology of calcium in myocardium, cardiac pacemakers, and vascular smooth muscle.
1977,
Pubmed Frank,
Early events in neuromuscular junction formation in vitro: induction of acetylcholine receptor clusters in the postsynaptic membrane and morphology of newly formed synapses.
1979,
Pubmed Gingell,
Changes in membrane impedance associated with a cortical contraction in the egg of Xenopus laevis.
1968,
Pubmed
,
Xenbase Gingell,
Contractile responses at the surface of an amphibian egg.
1970,
Pubmed Guerriero,
Production and characterization of an antibody to myosin light chain kinase and intracellular localization of the enzyme.
1981,
Pubmed Hagiwara,
Calcium channel.
1981,
Pubmed Hall,
Cytoplasmic actin in postsynaptic structures at the neuromuscular junction.
1981,
Pubmed Heuser,
Organization of acetylcholine receptors in quick-frozen, deep-etched, and rotary-replicated Torpedo postsynaptic membrane.
1979,
Pubmed Hidaka,
N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide, a calmodulin antagonist, inhibits cell proliferation.
1981,
Pubmed Horwitz,
Trifluoperazine inhibits phagocytosis in a macrophagelike cultured cell line.
1981,
Pubmed Kidokoro,
Synapse formation and neurotrophic effects on muscle cell lines.
1976,
Pubmed Kidokoro,
Changes in synaptic potential properties during acetylcholine receptor accumulation and neurospecific interactions in Xenopus nerve-muscle cell culture.
1980,
Pubmed
,
Xenbase McManaman,
The effect of calcium on acetylcholine receptor synthesis.
1981,
Pubmed Means,
Calmodulin--an intracellular calcium receptor.
1980,
Pubmed Meijer,
Calmodulin in starfish oocytes. I. Calmodulin antagonists inhibit meiosis reinitiation.
1981,
Pubmed Nelson,
Participation of calmodulin in immunoglobulin capping.
1982,
Pubmed Obata,
Development of neuromuscular transmission in culture with a variety of neurons and in the presence of cholinergic substances and tetrodotoxin.
1977,
Pubmed Peng,
Membrane particle aggregates in innervated and noninnervated cultures of Xenopus embryonic muscle cells.
1978,
Pubmed
,
Xenbase Peng,
Formation of ACh receptor clusters induced by positively charged latex beads.
1981,
Pubmed
,
Xenbase Peng,
Development of the postsynaptic membrane in Xenopus neuromuscular cultures observed by freeze-fracture and thin-section electron microscopy.
1980,
Pubmed
,
Xenbase Peng,
Formation of postsynaptic specializations induced by latex beads in cultured muscle cells.
1982,
Pubmed
,
Xenbase Peng,
Cytoskeletal organization of the presynaptic nerve terminal and the acetylcholine receptor cluster in cell cultures.
1983,
Pubmed
,
Xenbase Poo,
Rapid lateral diffusion of functional A Ch receptors in embryonic muscle cell membrane.
1982,
Pubmed
,
Xenbase Prives,
Interaction of the cytoskeletal framework with acetylcholine receptor on th surface of embryonic muscle cells in culture.
1982,
Pubmed Puro,
Synapse turnover: the formation and termination of transient synapses.
1977,
Pubmed Ravdin,
Fluorescent tetramethyl rhodamine derivatives of alpha-bungarotoxin: preparation, separation, and characterization.
1977,
Pubmed Salisbury,
Role of coated vesicles, microfilaments, and calmodulin in receptor-mediated endocytosis by cultured B lymphoblastoid cells.
1980,
Pubmed Weeds,
Actin-binding proteins--regulators of cell architecture and motility.
1982,
Pubmed Weiss,
Pharmacological regulation of calmodulin.
1980,
Pubmed
