Botulinum neurotoxin types A and E require the SNARE motif in SNAP‐25 for proteolysis

FEBS Letters

Montecucco, Cesare¹  Washbourne, Philip¹  Wilson, Michael C²  Baldini, Giulia³  Pellizzari, Rossella¹ 

[1] Centro C.N.R. Biomembrane and Dipartimento di Scienze Biomediche, Università di Padova, Via Colombo, 3, 35100 Padua, Italy;Dept. of Neurosciences, University of New Mexico, School of Medicine, Albuquerque, NM, USA;Dept. of Anatomy and Cell Biology, Columbia University, College of Physicians and Surgeons, New York, USA

关键词: SNAP-25;    Syndet;    SNARE motif;    Botulism;    Clostridium;    Neurotoxin;    Zinc endopeptidase;    BoNT;    botulinum neurotoxin;    DTT;    dithiothreitol;    GST;    glutathione S-methyl transferase;    SNAP-25;    synaptosome-associated protein of 25 kDa;    SNAREs;    soluble NSF accessory protein receptors;    TeNT;    tetanus toxin;    VAMP;    vesicle-associated membrane protein;   

DOI  :  10.1016/S0014-5793(97)01328-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Botulinum neurotoxins type A and E (BoNT/A and BoNT/E) are metalloproteases with a unique specificity for SNAP-25 (synaptosome-associated protein of 25 kDa), an essential protein component of the neuroexocytotic machinery. It has been suggested that this specificity is directed through the recognition of a nine residue sequence, termed SNARE motif, that is common to the other two SNARE proteins: VAMP (vesicle-associated membrane protein) and syntaxin, the only known substrates of the other six clostridial neurotoxins. Here we analyse the involvement of the four copies of the SNARE motif present in SNAP-25 in its interaction with BoNT/A and BoNT/E by following the kinetics of proteolysis of SNAP-25 mutants deleted of SNARE motifs. We show that a single copy of the motif is sufficient for BoNT/A and BoNT/E to recognise SNAP-25. While the copy of the motif proximal to the cleavage site is clearly involved in recognition, in its absence, other more distant copies of the motif are able to support proteolysis. Also, a non-neuronal isoform of SNAP-25, Syndet, is shown to be sensitive to BoNT/E, but not BoNT/A, whilst the SNAP-25 isoforms from Torpedo marmorata and Drosophila melanogaster were demonstrated not to be substrates of these metalloproteases.

【 授权许可】

Unknown