STRUCTURE AND FUNCTION OF RECEPTOR FOR CLOSTRIDIUM BOTULINUM TYPE B NEUROTOXIN

1995 Fiscal Year Final Research Report Summary

• Project/Area Number: 06660408
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: Applied veterinary science
• Research Institution: Osaka Prefecture University
• Principal Investigator: KOZAKI Shunji Osaka Prefecture University, Department of Agriculture, Associate Professor., 農学部, 助教授 (10109895)
• Co-Investigator(Kenkyū-buntansha): KAMATA Yoichi Osaka Prefecture University, Department of Agriculture, Research Associate., 農学部, 助手 (20152837)
• Project Period (FY): 1994 – 1995
• Keywords: Clostridium botulinum / neurotoxin / receptor

Research Abstract

Clostridium botulinum neurotoxin acts on nerve ending to inhibit neurotransmitter release. The toxin consists of heavy and light chains. The toxic action involves the binding to a type-specific receptor via the heavy chain, endocytosis, and translocation of the light chain into cytosol. We have identified the 58-kDa protein from rat brain synaptosomes, to which type B neurotoxin (BoNT/B) binds only in the presence of gangliosides GT1b/GD1a. Partial amino acid sequence revealed that the 58-kDa protein was identical to those of synaptotagmin, an integral membrane protein of synaptic vesicles. This results were also confirmed that BoNT/B bound specifically to recombinant rat synaptotagmins I and II.Scatchard plot analysis showed a single class of binding site with dissociation constants of 0.23 and 2.3 nM for synaptotagmin II and synaptotagmin I,respectively. The high-affinity binding of BoNT/B was specifically inhibited by a monoclonal antibody recognizing with the amino-terminal region of synaptotagmin II.Although the precise structure of the complex of synaptotagmin and gangliosides remains to be established, these findings indicate that synaptotagmin is a potential candidate acting as BoNT/B protein receptor.

Research Products

• [Publications] Nishiki,T. et al.: "Identification of protein receptor for clostridium botulinum type B neurotoxin in rat brain synaptosomes." Journal of Biological Chemistry. 269. 10498-10503 (1994)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Kamata,T. et al.: "The light chain of botulium neurotoxin forms channels in a lipid membrane." Biochemical and Biophysical Research Communication. 205. 751-757 (1994)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Nishiki,T. et al.: "The high-affinity binding of clostridium botulinum type B neurotoxin to synaptotagmin II associated with gangliosides GTlb/GDla." FEBS Letters. 378. 253-257 (1996)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] 小崎俊司: "ボツリヌス神経毒素の構造と作用発現機構" 日本細菌学雑誌. 51(印刷中). (1996)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Nishiki, T,Kamata, Y., Nemoto, Y., Omori, A., Ito, T., Takahashi, M., and Kozaki, S.: "Identification of protein receptor for Clostridium botulinum type B neurotoxin in rat brain synaptosomes." Journal of Biological Chemistry. 269. 10498-10503 (1994)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Kamata, Y., and Kozaki, S: "The light chain of botulinum neurotoxin forms channel in a lipid membrane" Biochem.Biophys.Res.Commun. 205. 751-757 (1994)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Nishiki, T., Tokuyama, Y., Kamata, Y.Nemoto, Y., Yoshida, A., Sato, K., Sekiguchi, M., Takahashi, M., and Kozaki, S: "The high-affinity binding of Clostridium botulinum type B neurotoxin to synaptotagmin II associated with ganglioside GT1b" FEBS Lett. 378. 253-257 (1996)
  • Description: 「研究成果報告書概要(欧文)」より