SNAP25
Description
The SNAP25 (synaptosome associated protein 25) is a protein-coding gene located on chromosome 20.
SNAP-25, also known as Synaptosomal-Associated Protein, 25kDa (SNAP-25), is a t-SNARE protein encoded by the SNAP25 gene found on chromosome 20p12.2 in humans. It is a key component of the trans-SNARE complex, which is responsible for the specificity of membrane fusion in the process of exocytosis. SNAP-25, a Q-SNARE protein, is anchored to the cytosolic face of membranes via palmitoyl side chains attached to cysteine residues in its central linker domain. It does not have a transmembrane domain. SNAP-25 contributes two α-helices to the SNARE complex, a four-α-helix domain structure. This complex is involved in vesicle fusion, which includes the docking, priming, and merging of a vesicle with the cell membrane. Along with synaptobrevin (VAMP) and syntaxin-1, SNAP-25 forms the SNARE complex, allowing for vesicle docking and fusion at active zones on the plasma membrane. The energy required for fusion is derived from the assembly of SNARE proteins and additional Sec1/Munc18-like (SM) proteins. The formation of the SNARE complex involves synaptobrevin, syntaxin-1, and SNAP-25 associating and wrapping around each other to create a coiled coil quaternary structure.
SNAP-25 plays a crucial role in neurotransmitter release by facilitating the fusion of synaptic vesicles with the plasma membrane. This process is essential for communication between neurons. It also participates in membrane recycling and influences the activity of potassium channels in pancreatic beta cells, suggesting its involvement in various cellular functions.
SNAP25 is also known as CMS18, RIC-4, RIC4, SEC9, SNAP, SNAP-25, SUP, bA416N4.2, dJ1068F16.2.