extrinsic component of synaptic vesicle membrane
Definition
Target type: cellularcomponent
The component of the synaptic vesicle membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region. [GOC:dos]
The extrinsic component of synaptic vesicle membrane refers to the proteins and other molecules that are associated with the outer leaflet of the synaptic vesicle membrane, but are not integral membrane proteins. These components play crucial roles in regulating vesicle trafficking, docking, and fusion, ultimately influencing neurotransmitter release at synapses.
Here's a detailed description of the components:
**1. SNARE proteins:**
* **Synaptobrevin (VAMP):** A transmembrane protein embedded in the vesicle membrane. It interacts with syntaxin and SNAP-25 on the presynaptic plasma membrane to form the SNARE complex, which drives vesicle fusion.
* **Synaptotagmin:** A calcium sensor protein that binds to the SNARE complex and triggers vesicle fusion upon calcium influx.
**2. Rab GTPases:**
* **Rab3A:** Regulates vesicle docking and priming at the active zone, a specialized region of the presynaptic membrane where neurotransmitter release occurs.
* **Rab27A:** Involved in vesicle tethering and docking, ensuring correct vesicle positioning for efficient release.
**3. Other proteins:**
* **Synapsin:** A protein that binds to synaptic vesicles and regulates their clustering and release probability.
* **Complexins:** Proteins that modulate SNARE complex assembly and fusion.
* **Munc13:** A protein that promotes SNARE complex formation and facilitates vesicle priming.
* **NSF and SNAP:** Chaperone proteins that disassemble the SNARE complex after fusion, allowing for vesicle recycling.
**4. Lipids:**
* **Phosphoinositides:** Lipids that are enriched in the synaptic vesicle membrane and play a role in vesicle trafficking and fusion.
* **Cholesterol:** A lipid that contributes to membrane fluidity and stability.
**5. Other molecules:**
* **Calcium ions:** Act as signaling molecules that trigger vesicle fusion.
* **Neurotransmitter molecules:** Encapsulated within the vesicle, awaiting release into the synaptic cleft.
These components work together in a highly coordinated manner to ensure efficient and precise neurotransmitter release, enabling communication between neurons.'
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Proteins (1)
| Protein | Definition | Taxonomy |
|---|---|---|
| V-type proton ATPase subunit B, brain isoform | A V-type proton ATPase subunit B, brain isoform that is encoded in the genome of human. [PRO:DNx, UniProtKB:P21281] | Homo sapiens (human) |
Compounds (1)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| enoxacin | enoxacin : A 1,8-naphthyridine derivative that is 1,4-dihydro-1,8-naphthyridine with an ethyl group at the 1 position, a carboxy group at the 3-position, an oxo sustituent at the 4-position, a fluoro substituent at the 5-position and a piperazin-1-yl group at the 7 position. An antibacterial, it is used in the treatment of urinary-tract infections and gonorrhoea. Enoxacin: A broad-spectrum 6-fluoronaphthyridinone antibacterial agent that is structurally related to NALIDIXIC ACID. | 1,8-naphthyridine derivative; amino acid; fluoroquinolone antibiotic; monocarboxylic acid; N-arylpiperazine; quinolone antibiotic | antibacterial drug; DNA synthesis inhibitor |