Proteolysis of SNAP-25 by types E and A botulinal neurotoxins.
Clostridial neurotoxins, tetanus toxin (TeTx) and the seven related but serologically distinct botulinal neurotoxins (BoNT/A to BoNT/G), are potent inhibitors of synaptic vesicle exocytosis in nerve endings. Recently it was reported that the light chains of clostridial neurotoxins act as zinc-dependent metalloproteases which specifically cleave synaptic target proteins such as synaptobrevin/VAMPs, HPC-1/syntaxin (BoNT/C1), and SNAP-25 (BoNT/A). We show here that BoNT/E, like BoNT/A, cleaves SNAP-25, as generated by in vitro translation or by expression in Escherichia coli. BoNT/E cleaves the Arg180-Ile181 bond. This site is different from that of BoNT/A, which cleaves SNAP-25 between the amino acid residues Gln197 and Arg198. These findings further support the view that clostridial neurotoxins have evolved from an ancestral protease recognizing the exocytotic fusion machinery of synaptic vesicles whereby individual toxins target different members of the membrane fusion complex.
Binz
T
T
Department of Microbiology, Federal Research Center of Virus Diseases of Animals, Tübingen, Germany.
Blasi
J
J
Yamasaki
S
S
Baumeister
A
A
Link
E
E
Südhof
T C
TC
Jahn
R
R
Niemann
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001905:Botulinum Toxins / Q000378:metabolism*; D001921:Brain / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D017931:DNA Primers; D015723:Gene Library; D008565:Membrane Proteins; D008666:Metalloendopeptidases / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D009498:Neurotoxins / Q000378:metabolism*; D016366:Open Reading Frames; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D014176:Protein Biosynthesis; D051381:Rats; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D015183:Restriction Mapping; D050825:Synaptosomal-Associated Protein 25; D014158:Transcription, Genetic
D017931:DNA Primers; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D009498:Neurotoxins; D010446:Peptide Fragments; D011994:Recombinant Proteins; C494209:Snap25 protein, mouse; C494210:Snap25 protein, rat; D050825:Synaptosomal-Associated Protein 25; D008666:Metalloendopeptidases; D001905:Botulinum Toxins