Synaptosomal Associated Protein 25kDa (SNAP25)

The SNAP-25 protein is a component of the SNARE complex, which is proposed to account for the specificity of membrane fusion and to directly execute fusion by forming a tight complex that brings the synaptic vesicle and plasma membranes together.SNAP-25 is a membrane bound protein anchored to the cytosolic face of membranes via palmitoyl side chains in the middle of the molecule. SNAP-25 is a Q-SNARE protein contributing two α-helices in the formation of the exocytotic fusion complex in neurons where it assembles with syntaxin-1 and synaptobrevin. SNAP-25 inhibits P/Q- and L-type voltage-gated calcium channels located presynaptically. and interacts with the synaptotagmin C2B domain in Ca²⁺-independent fashion. In glutamatergic synapses SNAP-25 decreases the Ca²⁺ responsiveness.