QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JCS Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Koticha, D. K. Articles by Baldini, G. Search for Related Content PubMed PubMed Citation Articles by Koticha, D. K. Articles by Baldini, G.

Plasma membrane targeting of SNAP-25 increases its local concentration and is necessary for SNARE complex formation and regulated exocytosis

Department of Anatomy and Cell Biology, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA

^* Author for correspondence (e-mail: gb74{at}columbia.edu )

Accepted 24 May 2002

SNAP-25 is an integral protein of the plasma membrane involved in neurotransmission and hormone secretion. The cysteine-rich domain of SNAP-25 is essential for membrane binding and plasma-membrane targeting. However, this domain is not required for SNARE complex formation and fusion of membranes in vitro. In this paper, we describe an `intact-cell'-based system designed to compare the effect of similar amounts of membrane-bound and soluble SNAP-25 proteins on regulated exocytosis. In transfected neuroblastoma cells, Botulinum neurotoxin E (BoNT/E), a protease that cleaves SNAP-25, blocks regulated release of hormone. However, hormone release is rescued by expressing a wild-type SNAP-25 protein resistant to the toxin. BoNT/E-resistant SNAP-25 proteins lacking the cysteine-rich domain or with all the cysteines substituted by alanines do not form SNARE complexes or rescue regulated exocytosis when expressed at the same level as membrane-bound SNAP-25, which is approximately four-fold higher than the endogenous protein. We conclude that the cysteine-rich domain of SNAP-25 is essential for Ca²⁺-dependent hormone release because, by targeting SNAP-25 to the plasma membrane, it increases its local concentration, leading to the formation of enough SNARE complexes to support exocytosis.

Key words: SNAP-25, Regulated exocytosis, Cysteine-rich domain

Related articles in JCS:

SNARE anchorage

JCS 2002 115: 1605. [Full Text]  

This article has been cited by other articles:

				G. Nagy, I. Milosevic, R. Mohrmann, K. Wiederhold, A. M. Walter, and J. B. Sorensen The SNAP-25 Linker as an Adaptation Toward Fast Exocytosis Mol. Biol. Cell, September 1, 2008; 19(9): 3769 - 3781. [Abstract] [Full Text] [PDF]

				S. Mohammad, G. Baldini, S. Granell, P. Narducci, A. M. Martelli, and G. Baldini Constitutive Traffic of Melanocortin-4 Receptor in Neuro2A Cells and Immortalized Hypothalamic Neurons J. Biol. Chem., February 16, 2007; 282(7): 4963 - 4974. [Abstract] [Full Text] [PDF]

				M. Holt, F. Varoqueaux, K. Wiederhold, S. Takamori, H. Urlaub, D. Fasshauer, and R. Jahn Identification of SNAP-47, a Novel Qbc-SNARE with Ubiquitous Expression J. Biol. Chem., June 23, 2006; 281(25): 17076 - 17083. [Abstract] [Full Text] [PDF]

				E. Reales, F. Mora-Lopez, V. Rivas, A. Garcia-Poley, J. A. Brieva, and A. Campos-Caro Identification of Soluble N-Ethylmaleimide-Sensitive Factor Attachment Protein Receptor Exocytotic Machinery in Human Plasma Cells: SNAP-23 Is Essential for Antibody Secretion J. Immunol., November 15, 2005; 175(10): 6686 - 6693. [Abstract] [Full Text] [PDF]

				G. Baldini, A. M. Martelli, G. Tabellini, C. Horn, K. Machaca, P. Narducci, and G. Baldini Rabphilin Localizes with the Cell Actin Cytoskeleton and Stimulates Association of Granules with F-actin Cross-linked by {alpha}-Actinin J. Biol. Chem., October 14, 2005; 280(41): 34974 - 34984. [Abstract] [Full Text] [PDF]

				R. Wiersma-Meems, J. Van Minnen, and N. I. Syed Synapse Formation and Plasticity: The Roles of Local Protein Synthesis Neuroscientist, June 1, 2005; 11(3): 228 - 237. [Abstract] [PDF]

				C. Salaun, G. W. Gould, and L. H. Chamberlain Lipid Raft Association of SNARE Proteins Regulates Exocytosis in PC12 Cells J. Biol. Chem., May 20, 2005; 280(20): 19449 - 19453. [Abstract] [Full Text] [PDF]

				M. Dong, W. H. Tepp, E. A. Johnson, and E. R. Chapman Using fluorescent sensors to detect botulinum neurotoxin activity in vitro and in living cells PNAS, October 12, 2004; 101(41): 14701 - 14706. [Abstract] [Full Text] [PDF]

				N.-J. Xu, Y.-X. Yu, J.-M. Zhu, H. Liu, L. Shen, R. Zeng, X. Zhang, and G. Pei Inhibition of SNAP-25 Phosphorylation at Ser187 Is Involved in Chronic Morphine-induced Down-regulation of SNARE Complex Formation J. Biol. Chem., September 24, 2004; 279(39): 40601 - 40608. [Abstract] [Full Text] [PDF]

				E. Chieregatti, M. C. Chicka, E. R. Chapman, and G. Baldini SNAP-23 Functions in Docking/Fusion of Granules at Low Ca2+ Mol. Biol. Cell, April 1, 2004; 15(4): 1918 - 1930. [Abstract] [Full Text] [PDF]

				J. G. Duman and J. G. Forte What is the role of SNARE proteins in membrane fusion? Am J Physiol Cell Physiol, August 1, 2003; 285(2): C237 - C249. [Abstract] [Full Text] [PDF]

				B. Pallavi and R. Nagaraj Palmitoylated Peptides from the Cysteine-rich Domain of SNAP-23 Cause Membrane Fusion Depending on Peptide Length, Position of Cysteines, and Extent of Palmitoylation J. Biol. Chem., April 4, 2003; 278(15): 12737 - 12744. [Abstract] [Full Text] [PDF]