Vesicle Fusion Events
Vesicle Fusion Events - Related Videos
01:26
Fusion of Secretory Vesicles with the Plasma Membrane
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2023
Proteins and neurotransmitters in secretory vesicles can be released from a cell upon vesicle docking, priming, and fusion with the plasma membrane. Vesicles are docked and primed in preparation for the quick exocytosis of their contents in response to a stimulus. The fusion process is mainly carried out by a SNAP Receptor or SNARE complex, consisting of synaptobrevin, syntaxin-1, and SNAP-25. In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
03:54
Total Internal Reflection Fluorescence Microscopy for Visualization of Exocytic Events
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2025
Source: Winkle, C. C., et al. Utilizing Combined Methodologies to Define the Role of Plasma Membrane Delivery During Axon Branching and Neuronal Morphogenesis. J. Vis. Exp. (2016)This video demonstrates total internal reflection fluorescence (TIRF) microscopy for visualizing exocytic events in cortical neurons. A pH-sensitive green fluorescent protein (GFP) marker fluoresces upon vesicle fusion, with selective TIRF excitation capturing membrane-proximal exocytosis in time-lapse imaging.
02:45
Nuclear Fusion
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2020
The process of converting very light nuclei into heavier nuclei is also accompanied by the conversion of mass into large amounts of energy, a process called fusion. The principal source of energy in the sun is a net fusion reaction in which four hydrogen nuclei fuse and ultimately produce one helium nucleus and two positrons. A helium nucleus has a mass that is 0.7% less than that of four hydrogen nuclei; this lost mass is converted into energy during the fusion. This reaction produces about...
09:19
Analysis of SNARE-mediated Membrane Fusion Using an Enzymatic Cell Fusion Assay
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2012
We have developed a cell fusion assay that quantifies SNARE-mediated membrane fusion events by activated expression of β-galactosidase.
10:58
SNARE-mediated Fusion of Single Proteoliposomes with Tethered Supported Bilayers in a Microfluidic Flow Cell Monitored by Polarized TIRF Microscopy
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Cited by 8 •
2016
Here, we present a protocol to detect single, SNARE-mediated fusion events between liposomes and supported bilayers in microfluidic channels using polarized TIRFM, with single molecule sensitivity and ~15 msec time resolution. Lipid and soluble cargo release can be detected simultaneously. Liposome size, lipid diffusivity, and fusion pore properties are measured.
FAQs
An action potential provides the initiating signal: it opens voltage-gated calcium channels at the presynaptic terminal. The resulting calcium entry supplies the trigger that links electrical activity to the molecular fusion machinery. This sequence explains how a neuronal signal is converted into neurotransmitter release with precise timing at the synapse.
Calcium, synaptotagmin, and SNARE proteins perform distinct but connected roles. Calcium binds synaptotagmin, which participates in the activation step, while SNARE proteins draw the vesicle and plasma membranes together. Their coordinated action is important because membrane approximation must progress to fusion-pore formation before neurotransmitters can leave the vesicle.
In neurons, vesicle fusion events serve communication by releasing neurotransmitters into the synaptic cleft. In the broader cellular setting, vesicles can instead deliver contents to a target membrane. This comparison distinguishes a specialized signaling outcome from the general transport role, while retaining the shared membrane-merging principle.
Rapid fusion events connect a transient electrical change with chemical signaling between neurons. Following calcium-channel opening, the downstream fusion sequence culminates in transmitter release into the synaptic cleft. Studying this timing helps explain how synapses transmit signals and how their behavior can adapt during learning.
Researchers can organize a neuronal event as a causal sequence: action-potential arrival, opening of voltage-gated calcium channels, calcium binding to synaptotagmin, SNARE-driven membrane approximation, fusion-pore formation, and neurotransmitter release. Examining this order clarifies which molecular step follows each electrical event and links the mechanism to synaptic output.
Studies of these events provide a mechanistic account of synaptic transmission rather than treating neurotransmitter release as an isolated endpoint. The sequence shows how presynaptic electrical activity engages calcium-dependent molecular machinery and produces chemical communication across the synaptic cleft. This makes vesicle fusion a useful framework for examining synaptic function and adaptation.
Vesicle fusion research is relevant to neurological disorders, neurotoxicity, and therapeutic development because abnormal neurotransmitter release can be examined through the fusion pathway. Comparing normal and disrupted events may connect changes in calcium-triggered membrane merger with altered synaptic communication. This framework supports both basic neuroscience and investigations of therapies targeting abnormal release.