Letter | Published:

Two modes of fusion pore opening revealed by cell-attached recordings at a synapse

Nature volume 444, pages 102105 (02 November 2006) | Download Citation

Subjects

Abstract

Fusion of a vesicle with the cell membrane opens a pore that releases transmitter to the extracellular space1,2,3. The pore can either dilate fully so that the vesicle collapses completely, or close rapidly to generate ‘kiss-and-run’ fusion1,2,4,5,6,7. The size of the pore determines the release rate2. At synapses, the size of the fusion pore is unclear, ‘kiss-and-run’ remains controversial8,9,10,11,12,13,14,15, and the ability of ‘kiss-and-run’ fusion to generate rapid synaptic currents16,17 is questionable18. Here, by recording fusion pore kinetics during single vesicle fusion, we found both full collapse and ‘kiss-and-run’ fusion at calyx-type synapses. For full collapse, the initial fusion pore conductance (Gp) was usually >375 pS and increased rapidly at ≥299 pS ms–1. ‘Kiss-and-run’ fusion was seen as a brief capacitance flicker (<2 s) with Gp >288 pS for most flickers, but within 15–288 pS for the remaining flickers. Large Gp (>288 pS) might discharge transmitter rapidly and thereby cause rapid synaptic currents, whereas small Gp might generate slow and small synaptic currents. These results show that ‘kiss-and-run’ fusion occurs at synapses and that it can generate rapid postsynaptic currents, and suggest that various fusion pore sizes help to control the kinetics and amplitude of synaptic currents.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    & Currents through the fusion pore that forms during exocytosis of a secretory vesicle. Nature 328, 814–817 (1987)

  2. 2.

    & The fusion pore. Biochim. Biophys. Acta 164, 167–173 (2003)

  3. 3.

    , & Release of secretory products during transient vesicle fusion. Nature 363, 554–558 (1993)

  4. 4.

    & Evidence for recycling of synaptic vesicle membrane during transmitter release at the frog neuromuscular junction. J. Cell Biol. 57, 315–344 (1973)

  5. 5.

    , & Turnover of transmitter and synaptic vesicles at the frog neuromuscular junction. J. Cell Biol. 57, 499–524 (1973)

  6. 6.

    , , & Neurotransmitter release, fusion or ‘kiss and run’?. Trends Cell Biol. 4, 1–4 (1994)

  7. 7.

    , & Capacitance measurements reveal stepwise fusion events in degranulating mast cells. Nature 312, 453–455 (1984)

  8. 8.

    , & Single synaptic vesicles fusing transiently and successively without loss of identity. Nature 423, 643–647 (2003)

  9. 9.

    & Three modes of synaptic vesicular recycling revealed by single-vesicle imaging. Nature 423, 607–613 (2003)

  10. 10.

    & The kinetics of synaptic vesicle pool depletion at CNS synaptic terminals. Neuron 41, 943–953 (2004)

  11. 11.

    , & Single and multiple vesicle fusion induce different rates of endocytosis at a central synapse. Nature 417, 555–559 (2002)

  12. 12.

    , & Vesicle endocytosis requires dynamin-dependent GTP hydrolysis at a fast CNS synapse. Science 307, 124–127 (2005)

  13. 13.

    , , , & Frequency-dependent kinetics and prevalence of kiss-and-run and reuse at hippocampal synapses studied with novel quenching methods. Neuron 49, 243–256 (2006)

  14. 14.

    & Vesicular proteins exocytosed and subsequently retrieved by compensatory endocytosis are nonidentical. Nature Neurosci. 9, 1019–1027 (2006)

  15. 15.

    , & Synaptic vesicles interchange their membrane proteins with a large surface reservoir during recycling. Neuron 51, 179–186 (2006)

  16. 16.

    , , , & Miniature endplate current rise times less than 100 microseconds from improved dual recordings can be modeled with passive acetylcholine diffusion from a synaptic vesicle. Proc. Natl Acad. Sci. USA 93, 5747–5752 (1996)

  17. 17.

    & Real-time measurement of transmitter release from single synaptic vesicles. Nature 377, 62–65 (1995)

  18. 18.

    & Capacitance steps and fusion pores of small and large-dense-core vesicles in nerve terminals. Nature 418, 89–92 (2002)

  19. 19.

    & The fine structure of nerve endings in the nucleus of the trapezoid body and the ventral cochlear nucleus. Am. J. Anat. 118, 375–390 (1966)

  20. 20.

    et al. Three-dimensional reconstruction of a calyx of Held and its postsynaptic principal neuron in the medial nucleus of the trapezoid body. J. Neurosci. 22, 10567–10579 (2002)

  21. 21.

    , & Direct measurement of specific membrane capacitance in neurons. Biophys. J. 79, 314–320 (2000)

  22. 22.

    , , & Coordinated multivesicular release at a mammalian ribbon synapse. Nature Neurosci. 7, 826–833 (2004)

  23. 23.

    & Resolution of patch capacitance recordings and of fusion pore conductances in small vesicles. Biophys. J. 78, 2983–2997 (2000)

  24. 24.

    , , , & in Synapses (eds Cowan, T. C., Sudhof, T. C. & Stevens, C. F.) 681–732 (Johns Hopkins Univ. Press, Baltimore, 2000)

  25. 25.

    et al. Limited numbers of recycling vesicles in small CNS nerve terminals: implications for neural signaling and vesicular cycling. Trends Neurosci. 24, 637–643 (2001)

  26. 26.

    , & Fusion pore modulation as a presynaptic mechanism contributing to expression of long-term potentiation. Phil. Trans. R. Soc. Lond. B 358, 695–705 (2003)

  27. 27.

    , & Postfusional control of quantal current shape. Neuron 42, 607–618 (2004)

  28. 28.

    et al. Millisecond studies of single membrane fusion events. Ann. NY Acad. Sci. 635, 318–327 (1991)

  29. 29.

    , , & Properties of the fusion pore that forms during exocytosis of a mast cell secretory vesicle. Neuron 4, 643–654 (1990)

  30. 30.

    , & Modulation of glutamate mobility reveals the mechanism underlying slow-rising AMPAR EPSCs and the diffusion coefficient in the synaptic cleft. Neuron 42, 757–771 (2004)

Download references

Acknowledgements

We thank V. Klyachko and M. Lindau for technical guidance on cell-attached recordings. We thank M. Lindau for the software for data analysis. We thank J. Diamond, W. Wu, L. Xue, W. Grimes, M. Diaz-Bustamante and B. McNeil for help with simulation and data analysis. We thank J. Diamond, D. Nees, K. Paradiso and J. Xu for comments on the manuscript. This work was supported by the National Institute of Neurological Disorders and Stroke Intramural Research Program.

Author information

Affiliations

  1. National Institute of Neurological Disorders and Stroke, 35 Convent Drive, Building 35, Room 2B-1012, Bethesda, Maryland 20892, USA

    • Liming He
    • , Xin-Sheng Wu
    • , Raja Mohan
    •  & Ling-Gang Wu

Authors

  1. Search for Liming He in:

  2. Search for Xin-Sheng Wu in:

  3. Search for Raja Mohan in:

  4. Search for Ling-Gang Wu in:

Competing interests

Reprints and permissions information is available at www.nature.com/reprints. The authors declare no competing financial interests.

Corresponding author

Correspondence to Ling-Gang Wu.

Supplementary information

PDF files

  1. 1.

    Supplementary Notes

    This file contains 8 sections: I) The debate of 'kiss-and-run' at synapses, II) Capacitance up-step frequency depends on calcium, III) The capacitance up-step or flicker was not caused by the capacitance artifact observed at the whole-cell mode, IV) Switch from the cell-attached to the whole-cell mode, V) Capacitance flickers reflect single vesicle fusion and retrieval, VI) Non-flicker up-steps with a small initial fusion pore conductance, VII) Fusion pore size affects the rate of transmitter release and thus the time course and the amplitude of synaptic currents, and VIII) Methods. This file also contains Supplementary Figures 1–10 and Supplementary Table 1.

About this article

Publication history

Received

Accepted

Published

DOI

https://doi.org/10.1038/nature05250

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.