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Two sites of action for synapsin domain E in regulating neurotransmitter release

A Correction to this article was published on 01 August 1998


Synapsins, a family of synaptic vesicle proteins, have been shown to regulate neurotransmitter release; the mechanism(s) by which they act are not fully understood. Here we have studied the role of domain E of synapsins in neurotransmitter release at the squid giant synapse. Two squid synapsin isoforms were cloned and found to contain a carboxy (C)-terminal domain homologous to domain E of the vertebrate a-type synapsin isoforms. Presynaptic injection of a peptide fragment of domain E greatly reduced the number of synaptic vesicles in the periphery of the active zone, and increased the rate and extent of synaptic depression, suggesting that domain E is essential for synapsins to regulate a reserve pool of synaptic vesicles. Domain E peptide had no effect on the number of docked synaptic vesicles, yet reversibly inhibited and slowed the kinetics of neurotransmitter release, indicating a second role for synapsins that is more intimately associated with the release process itself. Thus, synapsin domain E is involved in at least two distinct reactions that are crucial for exocytosis in presynaptic terminals.

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Figure 1: Identification and deduced primary structure of squid synapsins.
Figure 2: Domain E peptide inhibits neurotransmitter release.
Figure 3: Domain E peptide enhances synaptic depression, but has no effect on facilitation.
Figure 4: Domain E peptide decreases the number of synaptic vesicles.
Figure 5: Domain E peptide injection slows the kinetics of transmitter release.


  1. 1

    Rothman, J.E. Mechanisms of intracellular protein transport. Nature 372, 55–63 (1994)

    CAS  Article  Google Scholar 

  2. 2

    Südhof, T. C. The synaptic vesicle cycle: a cascade of protein-protein interactions. Nature 375, 645–653 (1995)

    Article  Google Scholar 

  3. 3

    Scheller, R.H. Membrane trafficking in the presynaptic nerve terminal. Neuron 14, 894–897 (1995)

    Google Scholar 

  4. 4

    Augustine, G. J., Burns, M. E., DeBello, W. M., Pettit, D. L. & Schweizer, F. E. Exocytosis: proteins and perturbations . Ann. Rev. Pharmacol. Toxicol. 36, 659– 701 (1996)

    CAS  Article  Google Scholar 

  5. 5

    Greengard, P., Valtorta, F., Czernik, A. J. & Benfenati, F. Synaptic vesicle phosphoproteins and regulation of synaptic function. Science 259, 780–785 (1993)

    CAS  Article  Google Scholar 

  6. 6

    Südhof et al. Synapsins: mosaics of shared and individual domains in a family of synaptic vesicle phosphoproteins . Science 245, 1474–1480 (1989)

    Article  Google Scholar 

  7. 7

    Kao, H.-T. et al. A third member of the synapsin gene family. Proc. Natl. Acad. Sci. USA 95, 4667–4672 (1998)

    CAS  Article  Google Scholar 

  8. 8

    Klagges, B. R. et al. Invertebrate synapsins: a single gene codes for several isoforms in Drosophila. J. Neurosci. 16, 3154–3165 (1996)

    CAS  Article  Google Scholar 

  9. 9

    Pieribone, V. A. et al. Distinct pools of synaptic vesicles in neurotransmitter release. Nature 375, 493–497 (1995)

    CAS  Article  Google Scholar 

  10. 10

    Rosahl, T. W. et al. Essential functions of synapsins I and II in synaptic vesicle regulation. Nature 375, 488–493 (1995)

    CAS  Article  Google Scholar 

  11. 11

    Rosahl, T. W. et al. Short-term synaptic plasticity is altered in mice lacking synapsin I. Cell 75, 661–670 (1993)

    CAS  Article  Google Scholar 

  12. 12

    Li, L. et al. Impairment of synaptic vesicle clustering and of synaptic transmission, and increased seizure propensity, in synapsin I-deficient mice. Proc. Natl. Acad. Sci. USA 92, 9235–9239 (1995)

    CAS  Article  Google Scholar 

  13. 13

    Takei, Y. et al. Synapsin I deficiency results in the structural change in the presynaptic terminals in the murine nervous system. J. Cell Biol. 131, 1789–1800 (1995)

    CAS  Article  Google Scholar 

  14. 14

    Ryan, T. A., Li, L., Chin, L.-S., Greengard, P. & Smith, S. J. Synaptic vesicle recycling in synapsin I knock-out mice. J. Cell Biol. 134, 1219– 1227 (1996)

    CAS  Article  Google Scholar 

  15. 15

    Llinás, R., McGuinness, T. L., Leonard, C. S., Sugimori, M. & Greengard, P. Intraterminal injection of synapsin I or calcium/calmodulin-dependent protein kinase II alters neurotransmitter release at the squid giant synapse. Proc. Natl. Acad. Sci. USA 82, 3035–3039 (1985)

    Article  Google Scholar 

  16. 16

    Llinás, R. Gruner, J. A., Sugimori, M., McGuinness, T. L. & Greengard, P. Regulation by synapsin I and Ca(2+)-calmodulin-dependent protein kinase II of the transmitter release in squid giant synapse. J. Physiol. 436, 257–282 (1991)

    Article  Google Scholar 

  17. 17

    Lin, J. W., Sugimori, M., Llinás, R. R., McGuinness, T. L. & Greengard, P. Effects of synapsin I and calcium/calmodulin-dependent protein kinase II on spontaneous neurotransmitter release in the squid giant synapse. Proc. Natl. Acad. Sci. USA 87, 8257–8261 (1990)

    CAS  Article  Google Scholar 

  18. 18

    Hackett, J. T., Cochran, S. L., Greenfield, J. Jr., Brosius, D. C. & Ueda, T. Synapsin I injected presynaptically into goldfish mauthner axons reduces quantal synaptic transmission . J. Neurophysiol. 63, 701– 706 (1990)

    CAS  Article  Google Scholar 

  19. 19

    Towbin, L., Staehelin, T. & Gordon, T. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc. Natl. Acad. Sci. USA 76, 4350–4354 (1979)

    CAS  Article  Google Scholar 

  20. 20

    Bommert, K. et al. Inhibition of neurotransmitter release by C2-domain peptides implicates synaptotagmin in exocytosis. Nature 363, 163– 165 (1993)

    CAS  Article  Google Scholar 

  21. 21

    Burns, M. E., Sasaki, T., Takai, Y. and Augustine, G.J. Rabphilin-3A: a multifunctional regulator of synaptic vesicle traffic. J. Gen. Physiol. 111, 243–255 (1998)

    CAS  Article  Google Scholar 

  22. 22

    Kusano, K. & Landau, E. M. Depression and recovery of transmission at the squid giant synapse. J. Physiol. 245, 13–32 (1975)

    CAS  Article  Google Scholar 

  23. 23

    Betz, W.J. Depression of transmitter release at the neuromuscular junction of the frog. J. Physiol. 206, 629–644 (1970)

    CAS  Article  Google Scholar 

  24. 24

    Swandulla, D., Hans, M., Zipser, K. & Augustine, G.J. Role of residual calcium in synaptic depression and posttetanic potentiation: fast and slow calcium signaling in nerve terminals. Neuron 7, 915–926 (1991)

    CAS  Article  Google Scholar 

  25. 25

    Charlton, M. P. & Bittner, G. D. Facilitation of transmitter release at squid synapses. J. Gen. Physiol. 72, 471–486 (1978)

    CAS  Article  Google Scholar 

  26. 26

    Zucker, R.S. Exocytosis: a molecular and physiological perspective. Neuron 17 , 1049–1055 (1996)

    CAS  Article  Google Scholar 

  27. 27

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

    CAS  Article  Google Scholar 

  28. 28

    Takei, K., Mundigl, O., Daniell, L. & De Camilli, P. The synaptic vesicle cycle: a single vesicle budding step involving clathrin and dynamin . J. Cell Biol. 133, 1237– 1250 (1996)

    CAS  Article  Google Scholar 

  29. 29

    Schweizer, F. E., Betz, H. & Augustine, G. J. From vesicle docking to endocytosis: intermediate reactions of exocytosis. Neuron 14, 689– 696 (1995)

    CAS  Article  Google Scholar 

  30. 30

    Parsons, T. D., Coorssen, J. R., Horstmann, H. & Almers, W. Docked granules, the exocytotic burst, and the need for ATP hydrolysis in endocrine cells. Neuron 15, 1085– 1096 (1995)

    CAS  Article  Google Scholar 

  31. 31

    Schikorski, T. & Stevens, C. F. Quantitative ultrastructural analysis of hippocampal excitatory synapses. J. Neurosci. 17 , 5858–5867 (1997)

    CAS  Article  Google Scholar 

  32. 32

    Hunt, J. M. et al. A post-docking role for synaptobrevin in synaptic vesicle fusion. Neuron 12, 1269–1279 (1994)

    CAS  Article  Google Scholar 

  33. 33

    Hess, S. D., Doroshenko, P. A. & Augustine, G. J. A functional role for GTP-binding proteins in synaptic vesicle cycling. Science 259, 1169– 1172 (1993)

    CAS  Article  Google Scholar 

  34. 34

    DeBello, W. M. et al. SNAP-mediated protein-protein interactions essential for neurotransmitter release. Nature 373, 626–630 (1995)

    CAS  Article  Google Scholar 

  35. 35

    Schweizer, F. E. et al. Regulation of neurotransmitter release kinetics by NSF. Science , 279, 1203–1206 (1998)

    CAS  Article  Google Scholar 

  36. 36

    O'Connor, V. et al. Disruption of syntaxin-mediated protein interactions blocks neurotransmitter secretion . Proc. Natl. Acad. Sci. USA 94, 12186– 12191 (1997)

    CAS  Article  Google Scholar 

  37. 37

    Hay, J. C. and Scheller, R. H. SNAREs and NSF in targeted membrane fusion. Curr. Opin. Cell Biol. 9, 505– 512 (1997)

    CAS  Article  Google Scholar 

  38. 38

    Söllner, T., Bennett, M. K., Whiteheart, S. W., Scheller, R. H. & Rothman, J. E. A protein assembly-disassembly pathway in vitro that may correspond to sequential steps of synaptic vesicle docking, activation and fusion. Cell 75, 409–418 (1993)

    Article  Google Scholar 

  39. 39

    Hirokawa, N., Sobue, K., Kanda, K., Harada, A. & Yorifuji, H. The cytoskeletal architecture of the presynaptic terminal and molecular structure of synapsin 1. J. Cell Biol. 108, 111–126 (1989)

    CAS  Article  Google Scholar 

  40. 40

    Valtorta, F. et al. Localization of synapsin I at the frog neuromuscular junction. Neurosci. 24, 593–603 (1988)

    CAS  Article  Google Scholar 

  41. 41

    Torri-Tarelli, F. et al. Redistribution of synaptophysin and synapsin I during α-latrotoxin-induced release of neurotransmitter at the neuromuscular junction. J. Cell Biol. 110, 449–459 (1990)

    CAS  Article  Google Scholar 

  42. 42

    Rahamimoff, R. and Fernandez, J. M. Pre- and postfusion regulation of transmitter release. Neuron 18, 17– 27 (1997)

    CAS  Article  Google Scholar 

  43. 43

    Vogel, S. S., Blank, P. S. and Zimmerberg, J. Poisson-distributed active fusion complexes underlie the control of the rate and extent of exocytosis by calcium. J. Cell Biol. 134, 329–338 (1996)

    CAS  Article  Google Scholar 

  44. 44

    Hong, R. M. et al. Association of N-ethylmaleimide-sensitive factor with synaptic vesicles. FEBS Lett. 350, 253–257 (1994)

    CAS  Article  Google Scholar 

  45. 45

    Esser, L. et al. Synapsin I is structurally similar to ATP-utilizing enzymes. EMBO J. 17, 977–984 (1998)

    CAS  Article  Google Scholar 

  46. 46

    Hosaka, M. & Südhof, T. Synapsins I and II are ATP-binding proteins with differential Ca regulation. J. Biol. Chem. 273, 1425–1429 (1998)

    CAS  Article  Google Scholar 

  47. 47

    Sanchez, M. E., Nuno, C. M., Buchanan, J. & Augustine, G.J. Contractions of the squid stellate ganglion. J. Exp. Biol. 152, 369–387 (1990)

    CAS  Google Scholar 

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We thank A. Jeromin and J. Battey for providing the squid stellate ganglion library, E. Buchner for providing the monoclonal antibody against Drosophila synapsin, S. Huber for EM image analysis, and J. Crawford for peptide synthesis. We are grateful to R. Rottenfusser (Zeiss), P. Bent (Nikon), and M. Delay (Axon Instruments) for loan of equipment and technical support. We also thank B. Finch and E. Griggs for help with the artwork, and V. Pieribone, T. Ryan and L. Brodin for advice and critical reading of the manuscript. Supported by a Grass Fellowship to S.H., The National Alliance for Research in Schizophrenia and Affective Disorders and The New York Community Trust by DeWitt-Wallace to H.-T. K., and NIH grants to P.G. and G.J.A.

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Correspondence to Paul Greengard.

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Hilfiker, S., Schweizer, F., Kao, HT. et al. Two sites of action for synapsin domain E in regulating neurotransmitter release. Nat Neurosci 1, 29–35 (1998).

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