Snapin: a SNARE-associated protein implicated in synaptic transmission.
Synaptic vesicle docking and fusion are mediated by the assembly of a stable SNARE core complex of proteins, which include the synaptic vesicle membrane protein VAMP/synaptobrevin and the plasmalemmal proteins syntaxin and SNAP-25. We have now identified another SNAP-25-binding protein, called Snapin. Snapin was enriched in neurons and exclusively located on synaptic vesicle membranes. It associated with the SNARE complex through direct interaction with SNAP-25. Binding of recombinant Snapin-CT to SNAP-25 blocked the association of the SNARE complex with synaptotagmin. Introduction of Snapin-CT and peptides containing the SNAP-25 binding sequence into presynaptic superior cervical ganglion neurons in culture reversibly inhibited synaptic transmission. These results suggest that Snapin is an important component of the neurotransmitter release process through its modulation of the sequential interactions between the SNAREs and synaptotagmin.
Ilardi
J M
JM
Synaptic Function Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, USA.
Mochida
S
S
Sheng
Z H
ZH
D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D002478:Cells, Cultured; D003001:Cloning, Molecular; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009474:Neurons / Q000502:physiology; D010446:Peptide Fragments / Q000502:physiology; D017729:Presynaptic Terminals / Q000502:physiology; D051381:Rats; D050600:SNARE Proteins; D013347:Subcellular Fractions / Q000378:metabolism; D017783:Superior Cervical Ganglion / Q000166:cytology / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology*; D013572:Synaptic Vesicles / Q000378:metabolism*; D050825:Synaptosomal-Associated Protein 25; D014018:Tissue Distribution; D033921:Vesicular Transport Proteins
D002352:Carrier Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D010446:Peptide Fragments; D050600:SNARE Proteins; C494210:Snap25 protein, rat; C498452:Snapin protein, rat; D050825:Synaptosomal-Associated Protein 25; D033921:Vesicular Transport Proteins