Skip to main content
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1988 May 1;106(5):1703–1712. doi: 10.1083/jcb.106.5.1703

A role for acetylcholine receptors in the fusion of chick myoblasts

PMCID: PMC2115056  PMID: 3372592

Abstract

The role of acetylcholine receptors in the control of chick myoblast fusion in culture has been explored. Spontaneous fusion of myoblasts was inhibited by the nicotinic acetylcholine receptor antagonists alpha- bungarotoxin, Naja naja toxin and monoclonal antibody mcAb 5.5. The muscarinic antagonists QNB and n-methyl scopolamine were without effect. Atropine had no effect below 1 microM, where it blocks muscarinic receptors; at higher concentrations, when it blocks nicotinic receptors also, atropine inhibited myoblast fusion. The inhibitions imposed by acetylcholine receptor antagonists lasted for approximately 12 h; fusion stimulated by other endogenous substances then took over. The inhibition was limited to myoblast fusion. The increases in cell number, DNA content, the level of creatine phosphokinase activity (both total and muscle-specific isozyme) and the appearance of heavy chain myosin, which accompany muscle differentiation, followed a normal time course. Pre-fusion myoblasts, fusing myoblasts, and young myotubes specifically bound labeled alpha- bungarotoxin, indicating the presence of acetylcholine receptors. The nicotinic acetylcholine receptor agonist, carbachol, induced uptake of [14C]Guanidinium through the acetylcholine receptor. Myoblasts, aligned myoblasts and young myotubes expressed the synthetic enzyme Choline acetyltransferase and stained positively with antibodies against acetylcholine. The appearance of ChAT activity in myogenic cultures was prevented by treatment with BUDR; nonmyogenic cells in the cultures expressed ChAT at a level which was too low to account for the activity in myogenic cultures. We conclude that activation of the nicotinic acetylcholine receptor is part of the mechanism controlling spontaneous myoblast fusion and that myoblasts synthesize an endogenous, fusion- inducing agent that activates the nicotinic ACh receptor.

Full Text

The Full Text of this article is available as a PDF (3.0 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Adams D. J., Bevan S. Some properties of acetylcholine receptors in human cultured myotubes. Proc R Soc Lond B Biol Sci. 1985 Apr 22;224(1235):183–196. doi: 10.1098/rspb.1985.0028. [DOI] [PubMed] [Google Scholar]
  2. Bevan S., Steinbach J. H. The distribution of alpha-bungarotoxin binding sites of mammalian skeletal muscle developing in vivo. J Physiol. 1977 May;267(1):195–213. doi: 10.1113/jphysiol.1977.sp011808. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Blum K., Seifter E., Seifter J. The pharmacology of d- and l-carnitine and d- and l-acetylcarnitine. Comparison with choline and acetylcholine. J Pharmacol Exp Ther. 1971 Aug;178(2):331–338. [PubMed] [Google Scholar]
  4. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
  5. David J. D., Higginbotham C. A. Fusion of chick embryo skeletal myoblasts: interactions of prostaglandin E1, adenosine 3':5' monophosphate, and calcium influx. Dev Biol. 1981 Mar;82(2):308–316. doi: 10.1016/0012-1606(81)90454-1. [DOI] [PubMed] [Google Scholar]
  6. Dwyer T. M., Adams D. J., Hille B. The permeability of the endplate channel to organic cations in frog muscle. J Gen Physiol. 1980 May;75(5):469–492. doi: 10.1085/jgp.75.5.469. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Entwistle A., Curtis D. H., Zalin R. J. Myoblast fusion is regulated by a prostanoid of the one series independently of a rise in cyclic AMP. J Cell Biol. 1986 Sep;103(3):857–866. doi: 10.1083/jcb.103.3.857. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Entwistle A., Zalin R. J., Bevan S., Warner A. E. The control of chick myoblast fusion by ion channels operated by prostaglandins and acetylcholine. J Cell Biol. 1988 May;106(5):1693–1702. doi: 10.1083/jcb.106.5.1693. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Fambrough D. M. Control of acetylcholine receptors in skeletal muscle. Physiol Rev. 1979 Jan;59(1):165–227. doi: 10.1152/physrev.1979.59.1.165. [DOI] [PubMed] [Google Scholar]
  10. Feltz A., Large W. A., Trautmann A. Analysis of atropine action at the frog neutromuscular junction. J Physiol. 1977 Jul;269(1):109–130. doi: 10.1113/jphysiol.1977.sp011895. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Fonnum F. A rapid radiochemical method for the determination of choline acetyltransferase. J Neurochem. 1975 Feb;24(2):407–409. doi: 10.1111/j.1471-4159.1975.tb11895.x. [DOI] [PubMed] [Google Scholar]
  12. Goodman D. R., Adatsi F. K., Harbison R. D. Evidence for the extreme overestimation of choline acetyltransferase in human sperm, human seminal plasma and rat heart: a case of mistaking carnitine acetyltransferase for choline acetyltransferase. Chem Biol Interact. 1984 Apr;49(1-2):39–53. doi: 10.1016/0009-2797(84)90051-6. [DOI] [PubMed] [Google Scholar]
  13. Hamprecht B., Amano T. Differential assay for choline acetyltransferase. Anal Biochem. 1974 Jan;57(1):162–172. doi: 10.1016/0003-2697(74)90062-1. [DOI] [PubMed] [Google Scholar]
  14. Hausman R. E., Dobi E. T., Woodford E. J., Petrides S., Ernst M., Nichols E. B. Prostaglandin binding activity and myoblast fusion in aggregates of avian myoblasts. Dev Biol. 1986 Jan;113(1):40–48. doi: 10.1016/0012-1606(86)90106-5. [DOI] [PubMed] [Google Scholar]
  15. Hume R. I., Honig M. G. Excitatory action of ATP on embryonic chick muscle. J Neurosci. 1986 Mar;6(3):681–690. doi: 10.1523/JNEUROSCI.06-03-00681.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Kolb H. A., Wakelam M. J. Transmitter-like action of ATP on patched membranes of cultured myoblasts and myotubes. Nature. 1983 Jun 16;303(5918):621–623. doi: 10.1038/303621a0. [DOI] [PubMed] [Google Scholar]
  17. Landmesser L. The development of motor projection patterns in the chick hind limb. J Physiol. 1978 Nov;284:391–414. doi: 10.1113/jphysiol.1978.sp012546. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Miledi R., Molenaar P. C., Polak R. L. An analysis of acetylcholine in frog muscle by mass fragmentography. Proc R Soc Lond B Biol Sci. 1977 Jun 15;197(1128):285–297. doi: 10.1098/rspb.1977.0071. [DOI] [PubMed] [Google Scholar]
  19. Miledi R., Molenaar P. C., Polak R. L., Tas J. W., van der Laaken T. Neural and non-neural acetylcholine in the rat diaphragm. Proc R Soc Lond B Biol Sci. 1982 Jan 22;214(1195):153–168. doi: 10.1098/rspb.1982.0002. [DOI] [PubMed] [Google Scholar]
  20. Rossier J. Choline acetyltransferase: a review with special reference to its cellular and subcellular localization. Int Rev Neurobiol. 1977;20:283–337. doi: 10.1016/s0074-7742(08)60656-x. [DOI] [PubMed] [Google Scholar]
  21. STOCKDALE F., OKAZAKI K., NAMEROFF M., HOLTZER H. 5-BROMODEOXYURIDINE: EFFECT ON MYOGENESIS IN VITRO. Science. 1964 Oct 23;146(3643):533–535. doi: 10.1126/science.146.3643.533. [DOI] [PubMed] [Google Scholar]
  22. Smilowitz H., Fischbach G. D. Acetylcholine receptors on chick mononucleated muscle precursor cells. Dev Biol. 1978 Oct;66(2):539–549. doi: 10.1016/0012-1606(78)90258-0. [DOI] [PubMed] [Google Scholar]
  23. Takeda K., Trautmann A. A patch-clamp study of the partial agonist actions of tubocurarine on rat myotubes. J Physiol. 1984 Apr;349:353–374. doi: 10.1113/jphysiol.1984.sp015160. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Tucek S., Havránek M., Ge I. Synthesis of [acetyl-14C]carnitine and the use of tetraphenylboron for differential extraction of [acetyl-14C]choline and [acetyl-14C]carnitine. Anal Biochem. 1978 Feb;84(2):589–593. doi: 10.1016/0003-2697(78)90080-5. [DOI] [PubMed] [Google Scholar]
  25. Young S. H., Poo M. M. Spontaneous release of transmitter from growth cones of embryonic neurones. Nature. 1983 Oct 13;305(5935):634–637. doi: 10.1038/305634a0. [DOI] [PubMed] [Google Scholar]
  26. Zalin R. J. Prostaglandins and myoblast fusion. Dev Biol. 1977 Sep;59(2):241–248. doi: 10.1016/0012-1606(77)90258-5. [DOI] [PubMed] [Google Scholar]
  27. Zalin R. J. The role of hormones and prostanoids in the in vitro proliferation and differentiation of human myoblasts. Exp Cell Res. 1987 Oct;172(2):265–281. doi: 10.1016/0014-4827(87)90386-7. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press

RESOURCES