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Syntaxin 1A drives fusion of large dense-core neurosecretory granules into a planar lipid bilayer

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Abstract

The SNARE complex, involved in vesicular trafficking and exocytosis, is composed of proteins in the vesicular membrane (v-SNAREs) that intertwine with proteins of the target membrane (t-SNAREs). Our results show that modified large dense-core neurosecretory granules (NSGs), isolated from the bovine neurohypophysis, spontaneously fuse with a planar lipid membrane containing only the t-SNARE syntaxin 1A. This provides evidence that syntaxin alone is able to form a functional fusion complex with native v-SNAREs of the NSG. The fusion was similar to constitutive, not regulated, exocytosis because changes in free [Ca2+] had no effect on the syntaxin-mediated fusion. Several deletion mutants of syntaxin 1A were also tested. The removal of the regulatory domain did not significantly reduce spontaneous fusion. However, a syntaxin deletion mutant consisting of only the transmembrane domain was incapable of eliciting spontaneous fusion. Finally, a soluble form of syntaxin 1A (lacking its transmembrane domain) was used to saturate the free syntaxin-binding sites of modified NSGs. This treatment blocks spontaneous fusion of these granules to a bilayer containing full-length syntaxin 1A. This method provides an effective model system to study possible regulatory components affecting vesicle fusion.

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References

  1. Woodbury, D. J. and Rognlien, K. (2000). Syntaxin: sufficient t-SNARE for spontaneous fusion of synaptic vesicles to planar membranes. Cell Biol. Int., 24(11), 809–818.

    Article  PubMed  CAS  Google Scholar 

  2. Rognlien, K. T. and Woodbury, D. J. (2003) Reconstituting SNARE proteins into BLMs, in Planar Lipid Bilayers (BLMs) and Their Applications Tien, H. T. and Ottova-Leitmannova, A., eds.), Membrane Science and Technology Series, Elsevier, Amsterdam, pp. 479–488.

    Chapter  Google Scholar 

  3. Woodbury, D. J. (1999b) Building a bilayer model of the synapse. Cell. Biochem. Biophys., 30, 303–329.

    Article  PubMed  CAS  Google Scholar 

  4. Jahn, R., Lang, T., and Sudhof, T. C. (2003) Membrane fusion. Cell, 112, 519–533.

    Article  PubMed  CAS  Google Scholar 

  5. Söllner, T., Whiteheart, S. W., Brunner, M., et al. (1993) SNAP receptors ilmplicated in vesicle targeting and fusion. Nature, 362, 318–324.

    Article  PubMed  Google Scholar 

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

    Article  PubMed  Google Scholar 

  7. Schiavo, G., Steinbeck, G., Rothman, J. E., and Söllner, T. H. (1997) Binding of the synaptic vesicle V-SNARE, SNAP-25, can explain docked vesicles at neurotoxin treated synapses. Proc. Natl. Acad. Sci. USA., 94, 997–1001.

    Article  PubMed  CAS  Google Scholar 

  8. Zhong, P., Chen, Y. A., Tan, D., Chung, D., Scheller, R. H., and Miljanich, G. P. (1997) An alpha-helical minimal binding domain within the H3 domain of syntaxin is required for SNAP-25 binding. Biochemistry, 36(14), 4317–43126.

    Article  PubMed  CAS  Google Scholar 

  9. Weber, T., Zemelman, B. V., McNew, J. A., et al., (1998) SNAREpins: minimal machinery for membrane fusion. Cell, 92, 759–772.

    Article  PubMed  CAS  Google Scholar 

  10. Hoffman, K. (1998) A model for structural similarity between different SNARE complexes based on sequence relationships. Cell Biol., 8, 260–262.

    Google Scholar 

  11. Ungerman, C., Nichols, B. J., Pelham, H. R. B., and Wickner, W. (1998) A vacuolor V-T-SNARE complex, the predominant form in vivo and on isolated vacuoles, is disassembled and activated for docking and fusion. J. Cell Biol., 40, 61–69.

    Article  Google Scholar 

  12. Parlati, F., Weber, T., McNew, J. A., Westermann, B., Sollner, T. H., and Rothman, J. E. (1999), rapid and efficient fusion of phospholipid vesicles by the alpha-helical core of a SNARE complex in the absence of an N-terminal regulatory domain. Proc. Natl. Acad. Sci. USA, 96(22), 12,565–12,570.

    Article  CAS  Google Scholar 

  13. Nicholson, K. L., Munson, M., Miller, R. B., Filip, T. J., Fairman, R., and Hughson, F. M. (1998) regulation of SNARE complex assembly by an N-terminal domain of the t-SNARE Sso1p. Naure Struct. Biol., 5(9), 793–803.

    Article  CAS  Google Scholar 

  14. Rizzo, J. and Sudhof, T. C. (2002) SNAREs and Munc18 in synaptic vesicle fusion. Nature Rev., 3, 641–653.

    Google Scholar 

  15. Hu, K., Carroll, J., Fedorovich, S., Rickman, C., Sukhodub, A., and Davletov, B. (2002) Vesicular restriction of synaptobrevin suggests a role for calcium in membrane fusion. Nature, 415(6872), 646–650.

    Article  PubMed  CAS  Google Scholar 

  16. Chapman, E. R. (2002) Synaptotagmin: a calcium sensor that triggers exocytosis? Nature Reviews., 3, 1–11.

    Google Scholar 

  17. Tucker, W. C., Weber, T., and Chapman, E. R. (2004) Reconstitution of calcium regulated membrane fusion by synaptotagmin and SNAREs. Science., 304, 435–438

    Article  PubMed  CAS  Google Scholar 

  18. Kelly, M. and Woodbury, D. J. (1996) Ion channels from synaptic vesicle membrane fragments reconstituted into lipid bilayer. Biophys. J., 70(6), 2593–2599.

    PubMed  CAS  Google Scholar 

  19. Perin, M. S. and MacDonald, R. C. (1989) Fusion of synaptic vesicle membranes with plenar bilayer membranes. Biophys. J., 55(5), 973–986.

    PubMed  CAS  Google Scholar 

  20. Woodbury, D. J. and Miller, C. (1990) Nystatin-induced liposome fusion: a versatile approach to ion channel reconstitution into planar bilayers. Biophys. J., 58, 833–839.

    Article  PubMed  CAS  Google Scholar 

  21. Woodbury, D. J. (1999) Nystatin/ergosterol method for reconstituting ion channels into planar lipid bilayers. Methods Enzymol., 294, 319–339.

    Article  PubMed  CAS  Google Scholar 

  22. Nordman, J. J., Louis, F., and Morris, S. J. (1979) Purification of two structurally and morphologically distinct populations of rat neurohypophysial secretory granules. Neuroscience, 4, 1367–1375d.

    Article  Google Scholar 

  23. Lee, C. J., Dayanithi, G., Nordmann J. J., and Lemos, J. R. (1992) Possible role during exocytosis of a Ca2+-activated channel in neurohy-pophysial granules. Neuron, 8, 335–342.

    Article  PubMed  CAS  Google Scholar 

  24. Lemos, J. R., Ocorr, K. A., and Nordman, J. J. (1989) Possible role during exocytosis of a Ca2+-activated channel in neurohypophysial granules. Neuron, 8, 335–342.

    Google Scholar 

  25. Stanley, E. F., Ehrenstein, G., and Russell, G. T. (1988) Evidence for anion channels in secretory vesicles. Neuroscience., 25, 1035–1039.

    Article  PubMed  CAS  Google Scholar 

  26. Yin, Y., Dayanithi, G., and Lemos, J. R. (2002) Ca2+-regulated synaptophysin-like channel involved in release from nerve terminals. J. Physiol. 539(2), 409–418d.

    Article  PubMed  CAS  Google Scholar 

  27. Woodbury, D. J. and Kelly, M. J. (1994) Release of ATP from cholinergic synaptic vesicles during freeze-thaw cycling. Cryobiology, 31, 279–289.

    Article  PubMed  CAS  Google Scholar 

  28. Langosch, D., Crane, J. M., Brossig, B., Hellwig, A., Tamm, L. K., and Reed, J. (2001) Peptide mimics of SNARE transmembrane segments drive membrane fusion depending on their conformational plasticity. J. Mol. Biol., 311, 709–721.

    Article  PubMed  CAS  Google Scholar 

  29. Fasshauer, D. (2003) Structural insights into the SNARE mechanism. Biochim. Biophys. Acta. 1641, 87–97.

    Article  PubMed  CAS  Google Scholar 

  30. McNally, J. M., Woodbury, D. J., and Lemos, J. R. (2003). Syntaxin mutants modulate fusion of dense core granules to a planar lipid bilayer. Biophys. J., 81, A950.

    Google Scholar 

  31. Poirier, M. A., Xiao, W., Macosko, J. C., Chan, C., Shin, Y., and Bennet, M. K. (1998) The synaptic SNARE complex is a parallel fourstranded helical bundle. Nature Struct. Biol. 5(9), 765–769.

    Article  PubMed  CAS  Google Scholar 

  32. Weis, W. I. and Scheller, R. H. (1998) Membrane fusion. SNARE the rod, coil the complex. Nature 395(67), 328–329.

    Article  PubMed  CAS  Google Scholar 

  33. Nichols, B. J., Ungermann, C., Pelham, H. R., Wickner, W. T., and Haas, A. (1997) Homotypic vacuolar fusion mediated by t- and v-SNAREs. Nature, 387(6629), 199–202.

    Article  PubMed  CAS  Google Scholar 

  34. Misura, K. M. S., Scheller, R. H., and Weis, W. I. (2001) Self association of the H3 region of syntaxin 1A. J. Biol. Chem., 276(16), 13,273–13,282.

    Article  CAS  Google Scholar 

  35. McNew, J. A., Weber, T., Parlati, F., et al. (2000). Close is not enough: SNARE-dependent membrane fusion requires an active mechanism that transduces force to membrane anchors. J. Cell Biol., 150(1), 105–117.

    Article  PubMed  CAS  Google Scholar 

  36. Melia, T. J., Weber, T., McNew, J. A., et al. (2002) Regulation of membrane fusion by the membrane-proximal coil of the t-SNARE during zippering of SNAREpins. J. Cell Biol., 158(8), 929–940.

    Article  PubMed  CAS  Google Scholar 

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Correspondence to José R. Lemos.

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McNally, J.M., Woodbury, D.J. & Lemos, J.R. Syntaxin 1A drives fusion of large dense-core neurosecretory granules into a planar lipid bilayer. Cell Biochem Biophys 41, 11–23 (2004). https://doi.org/10.1385/CBB:41:1:011

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