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. 1996 Jul 2;134(2):329–338. doi: 10.1083/jcb.134.2.329

Poisson-distributed active fusion complexes underlie the control of the rate and extent of exocytosis by calcium

PMCID: PMC2120878  PMID: 8707819

Abstract

We have investigated the consequences of having multiple fusion complexes on exocytotic granules, and have identified a new principle for interpreting the calcium dependence of calcium-triggered exocytosis. Strikingly different physiological responses to calcium are expected when active fusion complexes are distributed between granules in a deterministic or probabilistic manner. We have modeled these differences, and compared them with the calcium dependence of sea urchin egg cortical granule exocytosis. From the calcium dependence of cortical granule exocytosis, and from the exposure time and concentration dependence of N-ethylmaleimide inhibition, we determined that cortical granules do have spare active fusion complexes that are randomly distributed as a Poisson process among the population of granules. At high calcium concentrations, docking sites have on average nine active fusion complexes.

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Selected References

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  1. Adler E. M., Augustine G. J., Duffy S. N., Charlton M. P. Alien intracellular calcium chelators attenuate neurotransmitter release at the squid giant synapse. J Neurosci. 1991 Jun;11(6):1496–1507. doi: 10.1523/JNEUROSCI.11-06-01496.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Almers W. Synapses. How fast can you get? Nature. 1994 Feb 24;367(6465):682–683. doi: 10.1038/367682a0. [DOI] [PubMed] [Google Scholar]
  3. Augustine G. J., Neher E. Calcium requirements for secretion in bovine chromaffin cells. J Physiol. 1992 May;450:247–271. doi: 10.1113/jphysiol.1992.sp019126. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Baker P. F., Ravazzola M., Malaisse-Lagae F. Secretion-dependent uptake of extracellular fluid by the rat neurohypophysis. Nature. 1974 Jul 12;250(462):155–157. doi: 10.1038/250155a0. [DOI] [PubMed] [Google Scholar]
  5. Baker P. F., Whitaker M. J. Calcium-dependence of the cortical reaction in broken eggs of Echinus esculentus [proceedings]. J Physiol. 1978 Nov;284:50P–51P. [PubMed] [Google Scholar]
  6. Bennett M. K., Scheller R. H. A molecular description of synaptic vesicle membrane trafficking. Annu Rev Biochem. 1994;63:63–100. doi: 10.1146/annurev.bi.63.070194.000431. [DOI] [PubMed] [Google Scholar]
  7. Betz W. J., Mao F., Bewick G. S. Activity-dependent fluorescent staining and destaining of living vertebrate motor nerve terminals. J Neurosci. 1992 Feb;12(2):363–375. doi: 10.1523/JNEUROSCI.12-02-00363.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Chandler D. E. Exocytosis in vitro: ultrastructure of the isolated sea urchin egg cortex as seen in platinum replicas. J Ultrastruct Res. 1984 Nov;89(2):198–211. doi: 10.1016/s0022-5320(84)80015-5. [DOI] [PubMed] [Google Scholar]
  9. Chow R. H., Klingauf J., Neher E. Time course of Ca2+ concentration triggering exocytosis in neuroendocrine cells. Proc Natl Acad Sci U S A. 1994 Dec 20;91(26):12765–12769. doi: 10.1073/pnas.91.26.12765. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Crabb J. H., Jackson R. C. Polycation inhibition of exocytosis from sea urchin egg cortex. J Membr Biol. 1986;91(1):85–96. doi: 10.1007/BF01870218. [DOI] [PubMed] [Google Scholar]
  11. Douglas W. W. Involvement of calcium in exocytosis and the exocytosis--vesiculation sequence. Biochem Soc Symp. 1974;(39):1–28. [PubMed] [Google Scholar]
  12. Ferro-Novick S., Jahn R. Vesicle fusion from yeast to man. Nature. 1994 Jul 21;370(6486):191–193. doi: 10.1038/370191a0. [DOI] [PubMed] [Google Scholar]
  13. Geppert M., Goda Y., Hammer R. E., Li C., Rosahl T. W., Stevens C. F., Südhof T. C. Synaptotagmin I: a major Ca2+ sensor for transmitter release at a central synapse. Cell. 1994 Nov 18;79(4):717–727. doi: 10.1016/0092-8674(94)90556-8. [DOI] [PubMed] [Google Scholar]
  14. Guraya S. S. Recent progress in the structure, origin, composition, and function of cortical granules in animal egg. Int Rev Cytol. 1982;78:257–360. doi: 10.1016/s0074-7696(08)60108-4. [DOI] [PubMed] [Google Scholar]
  15. Haggerty J. G., Jackson R. C. Release of granule contents from sea urchin egg cortices. New assay procedures and inhibition by sulfhydryl-modifying reagents. J Biol Chem. 1983 Feb 10;258(3):1819–1825. [PubMed] [Google Scholar]
  16. Hammel I., Lagunoff D., Krüger P. G. Studies on the growth of mast cells in rats. Changes in granule size between 1 and 6 months. Lab Invest. 1988 Oct;59(4):549–554. [PubMed] [Google Scholar]
  17. Hammel I., Lagunoff D., Wysolmerski R. Theoretical considerations on the formation of secretory granules in the rat pancreas. Exp Cell Res. 1993 Jan;204(1):1–5. doi: 10.1006/excr.1993.1001. [DOI] [PubMed] [Google Scholar]
  18. Heidelberger R., Heinemann C., Neher E., Matthews G. Calcium dependence of the rate of exocytosis in a synaptic terminal. Nature. 1994 Oct 6;371(6497):513–515. doi: 10.1038/371513a0. [DOI] [PubMed] [Google Scholar]
  19. Heinemann C., von Rüden L., Chow R. H., Neher E. A two-step model of secretion control in neuroendocrine cells. Pflugers Arch. 1993 Jul;424(2):105–112. doi: 10.1007/BF00374600. [DOI] [PubMed] [Google Scholar]
  20. Heuser J. E., Reese T. S. Structural changes after transmitter release at the frog neuromuscular junction. J Cell Biol. 1981 Mar;88(3):564–580. doi: 10.1083/jcb.88.3.564. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Holz R. W., Bittner M. A., Peppers S. C., Senter R. A., Eberhard D. A. MgATP-independent and MgATP-dependent exocytosis. Evidence that MgATP primes adrenal chromaffin cells to undergo exocytosis. J Biol Chem. 1989 Apr 5;264(10):5412–5419. [PubMed] [Google Scholar]
  22. Horrigan F. T., Bookman R. J. Releasable pools and the kinetics of exocytosis in adrenal chromaffin cells. Neuron. 1994 Nov;13(5):1119–1129. doi: 10.1016/0896-6273(94)90050-7. [DOI] [PubMed] [Google Scholar]
  23. Jackson R. C., Ward K. K., Haggerty J. G. Mild proteolytic digestion restores exocytotic activity to N-ethylmaleimide-inactivated cell surface complex from sea urchin eggs. J Cell Biol. 1985 Jul;101(1):6–11. doi: 10.1083/jcb.101.1.6. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Jaffe L. A., Cross N. L. Electrical regulation of sperm-egg fusion. Annu Rev Physiol. 1986;48:191–200. doi: 10.1146/annurev.ph.48.030186.001203. [DOI] [PubMed] [Google Scholar]
  25. Kaplan D., Zimmerberg J., Puri A., Sarkar D. P., Blumenthal R. Single cell fusion events induced by influenza hemagglutinin: studies with rapid-flow, quantitative fluorescence microscopy. Exp Cell Res. 1991 Jul;195(1):137–144. doi: 10.1016/0014-4827(91)90509-s. [DOI] [PubMed] [Google Scholar]
  26. Katz B. Quantal mechanism of neural transmitter release. Science. 1971 Jul 9;173(3992):123–126. doi: 10.1126/science.173.3992.123. [DOI] [PubMed] [Google Scholar]
  27. Knight D. E., Baker P. F. Calcium-dependence of catecholamine release from bovine adrenal medullary cells after exposure to intense electric fields. J Membr Biol. 1982;68(2):107–140. doi: 10.1007/BF01872259. [DOI] [PubMed] [Google Scholar]
  28. Knight D. E., Baker P. F. Exocytosis from the vesicle viewpoint: an overview. Ann N Y Acad Sci. 1987;493:504–523. doi: 10.1111/j.1749-6632.1987.tb27237.x. [DOI] [PubMed] [Google Scholar]
  29. Kono T., Barham F. W. The relationship between the insulin-binding capacity of fat cells and the cellular response to insulin. Studies with intact and trypsin-treated fat cells. J Biol Chem. 1971 Oct 25;246(20):6210–6216. [PubMed] [Google Scholar]
  30. Koshland D. E., Jr, Némethy G., Filmer D. Comparison of experimental binding data and theoretical models in proteins containing subunits. Biochemistry. 1966 Jan;5(1):365–385. doi: 10.1021/bi00865a047. [DOI] [PubMed] [Google Scholar]
  31. Llinás R., Sugimori M., Silver R. B. Microdomains of high calcium concentration in a presynaptic terminal. Science. 1992 May 1;256(5057):677–679. doi: 10.1126/science.1350109. [DOI] [PubMed] [Google Scholar]
  32. MONOD J., WYMAN J., CHANGEUX J. P. ON THE NATURE OF ALLOSTERIC TRANSITIONS: A PLAUSIBLE MODEL. J Mol Biol. 1965 May;12:88–118. doi: 10.1016/s0022-2836(65)80285-6. [DOI] [PubMed] [Google Scholar]
  33. McLaughlin S., Whitaker M. Cations that alter surface potentials of lipid bilayers increase the calcium requirement for exocytosis in sea urchin eggs. J Physiol. 1988 Feb;396:189–204. doi: 10.1113/jphysiol.1988.sp016958. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Mohri T., Hamaguchi Y. Propagation of transient Ca2+ increase in sea urchin eggs upon fertilization and its regulation by microinjecting EGTA solution. Cell Struct Funct. 1991 Apr;16(2):157–165. doi: 10.1247/csf.16.157. [DOI] [PubMed] [Google Scholar]
  35. Mohri T., Hamaguchi Y. Quantitative analysis of the process and propagation of cortical granule breakdown in sea urchin eggs. Cell Struct Funct. 1990 Oct;15(5):309–315. doi: 10.1247/csf.15.309. [DOI] [PubMed] [Google Scholar]
  36. NICKERSON M. Receptor occupancy and tissue response. Nature. 1956 Sep 29;178(4535):697–698. doi: 10.1038/178697b0. [DOI] [PubMed] [Google Scholar]
  37. Neher E., Penner R. Mice sans synaptotagmin. Nature. 1994 Nov 24;372(6504):316–317. doi: 10.1038/372316a0. [DOI] [PubMed] [Google Scholar]
  38. Neher E., Zucker R. S. Multiple calcium-dependent processes related to secretion in bovine chromaffin cells. Neuron. 1993 Jan;10(1):21–30. doi: 10.1016/0896-6273(93)90238-m. [DOI] [PubMed] [Google Scholar]
  39. Neubig R. R., Cohen J. B. Permeability control by cholinergic receptors in Torpedo postsynaptic membranes: agonist dose-response relations measured at second and millisecond times. Biochemistry. 1980 Jun 10;19(12):2770–2779. doi: 10.1021/bi00553a036. [DOI] [PubMed] [Google Scholar]
  40. Roberts W. M., Jacobs R. A., Hudspeth A. J. Colocalization of ion channels involved in frequency selectivity and synaptic transmission at presynaptic active zones of hair cells. J Neurosci. 1990 Nov;10(11):3664–3684. doi: 10.1523/JNEUROSCI.10-11-03664.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Rothman J. E. Mechanisms of intracellular protein transport. Nature. 1994 Nov 3;372(6501):55–63. doi: 10.1038/372055a0. [DOI] [PubMed] [Google Scholar]
  42. STEPHENSON R. P. A modification of receptor theory. Br J Pharmacol Chemother. 1956 Dec;11(4):379–393. doi: 10.1111/j.1476-5381.1956.tb00006.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Thomas P., Lee A. K., Wong J. G., Almers W. A triggered mechanism retrieves membrane in seconds after Ca(2+)-stimulated exocytosis in single pituitary cells. J Cell Biol. 1994 Mar;124(5):667–675. doi: 10.1083/jcb.124.5.667. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Thomas P., Surprenant A., Almers W. Cytosolic Ca2+, exocytosis, and endocytosis in single melanotrophs of the rat pituitary. Neuron. 1990 Nov;5(5):723–733. doi: 10.1016/0896-6273(90)90226-6. [DOI] [PubMed] [Google Scholar]
  45. Thomas P., Wong J. G., Lee A. K., Almers W. A low affinity Ca2+ receptor controls the final steps in peptide secretion from pituitary melanotrophs. Neuron. 1993 Jul;11(1):93–104. doi: 10.1016/0896-6273(93)90274-u. [DOI] [PubMed] [Google Scholar]
  46. Vacquier V. D. The isolation of intact cortical granules from sea urchin eggs: calcium lons trigger granule discharge. Dev Biol. 1975 Mar;43(1):62–74. doi: 10.1016/0012-1606(75)90131-1. [DOI] [PubMed] [Google Scholar]
  47. Vogel S. S., Beushausen S., Lester D. S. Application of a membrane fusion assay for rapid drug screening. Pharm Res. 1995 Oct;12(10):1417–1422. doi: 10.1023/a:1016258615076. [DOI] [PubMed] [Google Scholar]
  48. Vogel S. S., Chernomordik L. V., Zimmerberg J. Calcium-triggered fusion of exocytotic granules requires proteins in only one membrane. J Biol Chem. 1992 Dec 25;267(36):25640–25643. [PubMed] [Google Scholar]
  49. Vogel S. S., Delaney K., Zimmerberg J. The sea urchin cortical reaction. A model system for studying the final steps of calcium-triggered vesicle fusion. Ann N Y Acad Sci. 1991;635:35–44. doi: 10.1111/j.1749-6632.1991.tb36479.x. [DOI] [PubMed] [Google Scholar]
  50. Vogel S. S., Leikina E. A., Chernomordik L. V. Lysophosphatidylcholine reversibly arrests exocytosis and viral fusion at a stage between triggering and membrane merger. J Biol Chem. 1993 Dec 5;268(34):25764–25768. [PubMed] [Google Scholar]
  51. Vogel S. S., Zimmerberg J. Proteins on exocytic vesicles mediate calcium-triggered fusion. Proc Natl Acad Sci U S A. 1992 May 15;89(10):4749–4753. doi: 10.1073/pnas.89.10.4749. [DOI] [PMC free article] [PubMed] [Google Scholar]
  52. Whalley T., Sokoloff A. The N-ethylmaleimide-sensitive protein thiol groups necessary for sea-urchin egg cortical-granule exocytosis are highly exposed to the medium and are required for triggering by Ca2+. Biochem J. 1994 Sep 1;302(Pt 2):391–396. doi: 10.1042/bj3020391. [DOI] [PMC free article] [PubMed] [Google Scholar]
  53. Whalley T., Terasaki M., Cho M. S., Vogel S. S. Direct membrane retrieval into large vesicles after exocytosis in sea urchin eggs. J Cell Biol. 1995 Dec;131(5):1183–1192. doi: 10.1083/jcb.131.5.1183. [DOI] [PMC free article] [PubMed] [Google Scholar]
  54. Zimmerberg J., Sardet C., Epel D. Exocytosis of sea urchin egg cortical vesicles in vitro is retarded by hyperosmotic sucrose: kinetics of fusion monitored by quantitative light-scattering microscopy. J Cell Biol. 1985 Dec;101(6):2398–2410. doi: 10.1083/jcb.101.6.2398. [DOI] [PMC free article] [PubMed] [Google Scholar]
  55. von Rüden L., Neher E. A Ca-dependent early step in the release of catecholamines from adrenal chromaffin cells. Science. 1993 Nov 12;262(5136):1061–1065. doi: 10.1126/science.8235626. [DOI] [PubMed] [Google Scholar]

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