Association of botulinum neurotoxin serotype A light chain with plasma membrane-bound SNAP-25. J Biol Chem 2011 Apr 29;286(17):15067-72
Date
03/08/2011Pubmed ID
21378164Pubmed Central ID
PMC3083167DOI
10.1074/jbc.M111.224493Scopus ID
2-s2.0-79955433958 (requires institutional sign-in at Scopus site) 35 CitationsAbstract
The Clostridium botulinum neurotoxins (BoNTs) cleave SNARE proteins, which inhibit binding and thus fusion of neurotransmitter vesicles to the plasma membrane of peripheral neurons. BoNTs comprise an N-terminal light chain (LC) and C-terminal heavy chain, which are linked by a disulfide bond. There are seven serotypes (A-G) of BoNTs based upon immunological neutralization. Although the binding and entry of BoNT/A into neurons has been subjected to considerable investigation, the intracellular events that allow BoNT/A to efficiently cleave SNAP-25 within neurons is less well understood. Earlier studies showed that intracellular LC/A bound to the plasma membrane of neurons. In this study, intracellular LC/A is shown to directly bind SNAP-25 on the plasma membrane. Solid phase binding showed that the N-terminal residues of LC/A bound residues 80-110 of SNAP-25, which was also observed in cultured neurons. Association of the N-terminal 8 amino acids of LC/A and residues 80-110 of SNAP-25 also enhanced substrate cleavage. These findings explain how LC/A associates with SNAP-25 on the plasma membrane and provide a basis for LC/A cleavage of SNAP-25 within the SNARE complex.
Author List
Chen S, Barbieri JTAuthor
Joseph T. Barbieri PhD Professor in the Microbiology and Immunology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsBinding Sites
Botulinum Toxins, Type A
Cell Line, Tumor
Cell Membrane
Clostridium botulinum
Hydrolysis
Mice
Neurons
Neurotoxins
Protein Binding
Synaptosomal-Associated Protein 25