SNAP-25 is the major immunoreactive component of the brain-specific D3 protein.
The rat synaptosomal membrane antigen D3, which has been studied for more than 20 years since its first demonstration as a brain-specific protein, was shown to bind monoclonal antibodies to SNAP-25, a presynaptic plasma membrane-associated protein. In addition to SNAP-25, anti-D3 antiserum also precipitated two polypeptides of 34-36 kDa and 14-16 kDa. This suggests that anti-D3 binds all three of the 20S synaptic vesicle fusion particle components, i.e. SNAP-25, syntaxin, and vesicle-associated membrane protein (VAMP)/synaptobrevin. However, the botulinum toxins C and D, which are endoproteases selective for syntaxin and VAMP/synptobrevin, respectively, were unable to remove the D3 immunoreactivity from synaptosomal membranes. Therefore, it is concluded that D3 immunoreactivity is directed only against SNAP-25.
Jørgensen
O S
OS
Department of Pharmacology, University of Copenhagen, Denmark.
D000595:Amino Acid Sequence; D000704:Analysis of Variance; D000818:Animals; D003902:Detergents; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000032:analysis* / Q000737:chemistry*; D009479:Neuropeptides / Q000737:chemistry*; D017830:Octoxynol; D051381:Rats; D012995:Solubility; D050825:Synaptosomal-Associated Protein 25
D003902:Detergents; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; C494210:Snap25 protein, rat; D050825:Synaptosomal-Associated Protein 25; C028117:nervous tissue specific protein D3; D017830:Octoxynol