肉毒神经毒素受体的研究进展

Studies on The Receptors of Botulinum Neurotoxins

肉毒神经毒素(botulinumneurotoxin)是世界已知毒性最强的生物毒素,它通过酶切在递质释放过程中起关键作用的SNARE蛋白,抑制神经递质释放,阻断突触传递.综述了有关肉毒受体研究的进展.这些研究表明,肉毒的结合位点有低亲和力的和高亲和力的两种.肉毒的结合过程分两步,它首先与细胞表面的神经节苷脂结合,形成低亲和力的聚合体,然后再与高亲和力的蛋白受体——synaptotagmin结合,形成牢固的三聚体结构,并由内吞进入细胞.这种解释肉毒结合过程的双受体学说得到了越来越多的支持,文中列举和评述了支持该学说的实验资料.

Botulinum neurotoxin（BoNT） is the most lethal biotoxin known to mankind. It inhibits acetylcholine release from the cholinergic nerve ending by cleavage of SNARE proteins, followed by neuromuscular blockade and paralysis. Gangliosides are considered to act as a first receptor of BoNT with low affinity.Then the membrane bound gangliosides-BoNT complex moves laterally to reach and bind the toxin specific protein receptor, synaptotagmin, with a high affinity constant. At last the gangliosides-BoNT-synaptotagmin complex undergoes receptor-mediated endocytosis. This double-receptors theory is widely accepted. The research data are summarized and reviewed.