STRUCTURE AND FUNCTION OF RECEPTOR FOR CLOSTRIDIUM BOTULINUM TYPE B NEUROTOXIN

B 型肉毒梭菌神经毒素受体的结构和功能

• 批准号: 06660408
• 负责人: KOZAKI Shunji
• 金额: $ 1.28万
• 依托单位: Osaka Prefecture University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06660408/
• 关键词: Clostridium botulinum; neurotoxin; receptor

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.

肉毒杆菌神经毒素作用于神经末梢，抑制神经递质释放。该毒素由重链和轻链组成。毒性作用涉及通过重链、内吞作用和轻链易位到细胞质中与类型特异性受体结合。我们从大鼠脑突触体中鉴定出了 58 kDa 的蛋白质，B 型神经毒素 (BoNT/B) 仅在神经节苷脂 GT1b/GD1a 存在的情况下才能与其结合。部分氨基酸序列显示，58 kDa 的蛋白质与突触结合蛋白（突触小泡的整合膜蛋白）的氨基酸序列相同。这一结果也证实了 BoNT/B 与重组大鼠突触结合蛋白 I 和 II 特异性结合。斯卡查德图分析显示突触结合蛋白 II 和突触结合蛋白 I 的解离常数分别为 0.23 和 2.3 nM 的单一类别结合位点。 BoNT/B 的高亲和力结合被识别突触结合蛋白 II 氨基末端区域的单克隆抗体特异性抑制。虽然突触结合蛋白和神经节苷脂复合物的精确结构仍有待确定，但这些发现表明突触结合蛋白是一种作为 BoNT/B 蛋白受体的潜在候选者。

项目成果

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)

西木，T.

Nishiki T.,et al.: "The high-affinity binding of Clostridium botulinum type B neurotoxin to synaptotagmin II associated with gangliosides GT1b/GD1a." FEBS Letters. 378. 253-257 (1996)

Nishiki T.,et al.：“B 型肉毒杆菌神经毒素与神经节苷脂 GT1b/GD1a 相关的突触结合蛋白 II 的高亲和力结合。”

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)

Kamata, Y. 和 Kozaki, S：“肉毒杆菌神经毒素的轻链在脂质膜中形成通道”Biochem.Biophys.Res.Commun。

Nishiki T.,et al.: "Identification of protein receptor for clostridium butulium type B neurotoxin in rat brain synaptosomes." Journal of Biological Chemistry. 269. 10498-10503 (1994)

Nishiki T.,et al.：“大鼠脑突触体中丁氏梭菌 B 型神经毒素蛋白受体的鉴定。”

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

Nishiki, T.、Tokuyama, Y.、Kamata, Y.Nemoto, Y.、Yoshida, A.、Sato, K.、Sekiguchi, M.、Takahashi, M. 和 Kozaki, S：“高亲和力结合