Calcium-Triggered Exocytosis and Clathrin-Mediated Endocytosis of Synaptic Vesicles
Thierry Galli1*andVolker Haucke2*
*Corresponding author. E-mail, (T.G.) or (V.H.)
Animation 1. A model for fast-track exocytosis of synaptic vesicles. In this model of vesicle fusion and recycling, the synaptic vesicles stay in close proximity to the plasma membrane. The animation shows vesicle attachment through loose SNARE complexes between synaptobrevin, syntaxin1, and SNAP-25. Calcium entry triggers a conformational change in synaptotagmin 1 that promotes the formation of a tight SNARE complex, which leads to the hemifusion stage of lipid bilayer fusion followed by the opening of a lipid-made fusion pore and release of neurotransmitter. An unknown mechanism prevents the SNARE complex from dissociating further, thus preventing full fusion and concomitant insertion of synaptic vesicle proteins into the presynaptic plasma membrane. SNAPs (not shown) and N-ethylmaleimide sensitive factor catalyze the reversion of tight complexes into incompletely disassembled SNARE complexes, and conformational changes in dynamin close the lipid-made fusion pore. Finally, the proton pump restores the electrochemical gradient (not shown) and the vesicles are refilled with neurotransmitter and can undergo another cycle of release.
Use the buttons to proceed through the animation, to step back, or to restart.
The animation was created by Cameron Slayden under the direction of Thierry Galli and Volker Haucke.
The animation would be useful in illustrating a model for partial release of vesicle content through a calcium-triggered process using the synaptic vesicle as a model. Thus, the animation could be useful in neurobiology, cell biology, and biochemistry courses.
Learning Resource Type: Animation
Context: Undergraduate upper division, graduate, professional (degree program)
Intended Users: Teacher, learner
Intended Educational Use: Teach, learn
Discipline: Biochemistry, cell biology, neurobiology
Keywords: Kiss-and-run, exocytosis, vesicle, synapse, SNARE
Format: Shockwave Flash Objects (swf file)
Size: 71 kb
Requirements: This animation will play with Macromedia Flash 5 or higher (http://www.macromedia.com/downloads/).
Limits for Use
Rights: This material may be downloaded, printed, linked to, and/or redistributed without modification for noncommercial, course-teaching purposes only, provided credit to STKE is included by listing the citation for the teaching resource.
Citation: T. Galli, V. Haucke, A model for fast-track exocytosis of synaptic vesicles. Sci. STKE2005, tr1 (2005).