Skip to main content
Log in

Monte Carlo simulations of membrane signal transduction events: Effect of receptor blockers on G-protein activation

  • Research Articles
  • Published:
Annals of Biomedical Engineering Aims and scope Submit manuscript

Abstract

Cells have evolved elaborate strategies for sensing, responding to, and interacting with their environment. In many systems, interaction of cell surface receptors with extracellular ligand can activate cellular signal transduction pathways leading to G-protein activation and calcium mobilization. In BC3H1 smooth muscle-like cells, we find that the speed of calcium mobilization as well as the fraction of cells which mobilize calcium following phenylephrine stimulation is dependent upon receptor occupation. To determine whether receptor inactivation affects calcium mobilization, we use the receptor antagonist prazosin to block a fraction of cell surface receptors prior to phenylephrine stimulation. For cases of equal receptor occupation by agonist, cells with inactivated or blocked receptors show diminished calcium mobilization following phenylephrine stimulation as compared to cells without inactivated receptors. Ligand/receptor binding and two-dimensional diffusion of receptors and G-proteins in the cell membrane are studied using a Monte Carlo model. The model is used to determine if receptor inactivation affects G-protein activation and thus the following signaling events for cases of equal equilibrium receptor occupation by agonist. The model predicts that receptor inactivation by antagonist binding results in lower G-protein activation not only by reducing the number of receptors able to bind agonist but also by restricting the movement of agonist among free receptors. The latter process is important to increasing the access of bound receptors to G-proteins.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Abel, P. W., and K. P. Minneman.Alpha-1 adrenergic receptor binding and contraction of rat caudal artery.J. Pharmacol. Exp. Ther. 239(3):678–686, 1986.

    PubMed  CAS  Google Scholar 

  2. Alberts, B., D. Bray, J. Lewis, M. Raff, K. Roberts, and J. D. Watson. Molecular Biology of the Cell. New York: Garland Publishing, Inc., 1989, 1219 pp.

    Google Scholar 

  3. Amitai, G., R. D. Brown, and P. Taylor. The relationship between α1-adrenergic receptor occupation and the mobilization of intracellular calcium.J. Biol. Chem. 259(20): 12519–12527, 1984.

    PubMed  CAS  Google Scholar 

  4. Bakardjieva, A., H. J. Galla, and E. J. M. Helmreich. Modulation of the β-receptor adenylate cyclase interactions in cultured chang liver cells by phospholipid enrichment.Biochemistry 18(14):3016–3023, 1979.

    Article  PubMed  CAS  Google Scholar 

  5. M. J. Berridge. Inositol trisphosphate and calcium signalling.Nature 361:315–325, 1993.

    Article  PubMed  CAS  Google Scholar 

  6. Bokoch, G. M., K. Bickford, and B. P. Bohl. Subcellular localization and quantitation of the major neutrophil pertussis toxin substrate, G n .J. Cell Biol. 106:1927–1936, 1988.

    Article  PubMed  CAS  Google Scholar 

  7. Brown, R. D., K. D. Berger, and P. Taylor. α1-Adrenergic receptor activation mobilizes cellular Ca2+ in a muscle cell line.J. Biol. Chem. 259(12):7554–7562, 1984.

    PubMed  CAS  Google Scholar 

  8. Dalman, H. M., and R. R. Neubig. Two peptides from the alpha2A -adrenergic receptor alter receptor G protein coupling by distinct mechanisms.J. Biol. Chem. 266:11025–11029, 1991.

    PubMed  CAS  Google Scholar 

  9. Dembo, A., A. Kagey-Sobotka, L. M. Lichtenstein, and B. Goldstein. Kinetic analysis of histamine release due to covalently linked IgE dimers.Mol. Immunol. 19:421–434, 1982.

    Article  PubMed  CAS  Google Scholar 

  10. Gennis, R. R.Biomembranes: Molecular Structure and Function. Springer-Verlag, 1989, 533 pp.

  11. Goldstein, B., C. Wofsy, and G. Bell. Interactions of low density lipoprotein receptors with coated pits on human fibroblasts: Estimate of the forward rate constant and comparison with the diffusion limit.Cell Biol. 78(9):5695–5698, 1981.

    CAS  Google Scholar 

  12. Gorospe, W. C., and P. M. Conn. Membrane fluidity regulates development of gonadotrope desensitization to GnRH.Mol. Cell. Endocrinol. 52:131–140, 1987.

    Article  Google Scholar 

  13. Grynkiewicz, G., M. Poenie, and R. Y. Tsien. A new generation of Ca2+ indicators with greatly improved fluorescence properties.J. Biol. Chem. 260(6):3440–3450, 1985.

    PubMed  CAS  Google Scholar 

  14. Guellaen, G., M. Yates-Aggerbeck, G. Vauquelin, D. Strosberg, and J. Hanoune. Characterization with [3H]dihydroergocryptine of the α-adrenergic receptor of the hepatic plasma membrane.J. Biol. Chem. 253(4):1114–1120, 1978.

    PubMed  CAS  Google Scholar 

  15. Hanski, E., G. Rimon, and A. Levitzki. Adenylate cyclase activation by the β-adrenergic receptors as a diffusion-controlled process.Biochemistry 18(5):846–853, 1979.

    Article  PubMed  CAS  Google Scholar 

  16. Hughes, R. J., M. R. Boyle, R. D. Brown, P. Taylor, and P. A. Insel. Characterization of coexistingAlpha 1- andBeta 2-adrenergic receptors on a cloned muscle cell line, BC3H1.Mol. Pharmacol. 22(2):258–266, 1982.

    PubMed  CAS  Google Scholar 

  17. Kwon, G., R. R. Neubig, and D. Axelrod. Lateral mobility of tetramethylrhodamine labeled g protein βγ subunits in NG-108-15 cells.FASEB J. 5:A1595, 1991.

    Google Scholar 

  18. Lauffenburger, D. A., and J. J. Linderman. Receptors: Models for Binding, Trafficking, and Signaling. New York: Oxford University Press, 1993, 365 pp.

    Google Scholar 

  19. Mahama, P. A., and J. J. Linderman. Calcium signaling in individual BC3H1 cells: Speed of calcium mobilization and heterogeneity.Biotech. Prog. 10:45–54, 1994.

    Article  CAS  Google Scholar 

  20. Mahama, P. A., and J. J. Linderman. A Monte Carlo study of the dynamics of G-protein activation.Biophys. J. 67:1345–1357, 1994.

    PubMed  CAS  Google Scholar 

  21. Mauger, J. P., F. Sladeczek, and J. Bockaert. Characteristics and metabolism of α1 adrenergic receptors in a nonfusing muscle cell line.J. Biol. Chem. 257(2):875–879, 1982.

    PubMed  CAS  Google Scholar 

  22. Mayo, K. H., M. Nunez, C. Burke, C. Starbuck, D. Lauffenburger, and C. R. Savage, Jr. Epidermal growth factor receptor binding is not a simple one-step process.J. Biol. Chem. 264:17838–17844, 1989.

    PubMed  CAS  Google Scholar 

  23. Moscona-Amir, E., Y. I. Henis, and M. Sokolovsky. Aging of rat heart myocytes disrupts muscarinic receptor coupling that leads to inhibition of cAMP accumulation and alters the pathway of muscarinic-stimulated phosphoinositide hydrolysis.Biochemistry 28(17):7130–7137, 1989.

    Article  PubMed  CAS  Google Scholar 

  24. Stickle, D., and R. Barber. Evidence for the role of epinephrine binding frequency in activation of adenylate cyclase.Mol. Pharmacol. 36:437–445, 1989.

    PubMed  CAS  Google Scholar 

  25. Stickle, D., and R. Barber. The encounter coupling model for beta-adrenergic receptor/GTP-binding protein interaction in the S49 cell. Calculation of the encounter frequency.Biochem. Pharmacol. 43(9):2015–2028, 1992.

    Article  PubMed  CAS  Google Scholar 

  26. Stickle, D., and R. Barber. Analysis of receptor-mediated activation of GTP-binding protein/adenylate cyclase using the encounter coupling model.Mol. Pharmacol. 43:397–411, 1993.

    PubMed  CAS  Google Scholar 

  27. Taylor, C. W. The role of G proteins in transmembrane signalling.Biochem. J. 272;1–13, 1990.

    PubMed  CAS  Google Scholar 

  28. Thomsen, W. J. and R. R. Neubig. Rapid kinetics of α2-adrenergic inhibition of adenylate cyclase. Evidence for a distal rate-limiting step.Biochemistry 28(22):8778–8786, 1989.

    Article  PubMed  CAS  Google Scholar 

  29. Torney, D. C., and H. M. McConnell. Diffusion-limited reaction rate theory for two-dimensional systems.Proc. R. Soc. Lond. A, 387:147–170, 1983.

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Mahama, P.A., Linderman, J.J. Monte Carlo simulations of membrane signal transduction events: Effect of receptor blockers on G-protein activation. Ann Biomed Eng 23, 299–307 (1995). https://doi.org/10.1007/BF02584430

Download citation

  • Received:

  • Revised:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02584430

Keywords

Navigation