Structural and functional studies of botulinum neurotoxin

肉毒杆菌神经毒素的结构和功能研究

• 批准号: 8655919
• 负责人: Rongsheng Jin
• 金额: $ 23万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-12-15 至 2016-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8655919
• 关键词: Accounting; Adverse drug effect; Affect; Affinity; Architecture; Bacteria; Binding; Biochemistry; Bioinformatics; Biophysics; Bioterrorism; Blood Circulation; Bontoxilysin; Botox; Botulinum Toxin Type A; Botulism; Cells; Cellular biology; Chronic; Cleaved cell; Clinical; Clostridium botulinum; Complex; Cosmetics; Development; Drug Delivery Systems; Drug Formulations; Elan brand of botulinum toxin type B; Environment; Enzymes; Epithelial; Epithelial Cells; Exocytosis; FDA approved; Food; Gastrointestinal Diseases; Gastrointestinal tract structure; Gills; Goals; Hemagglutinin; Ingestion; Intestines; Intoxication; Lead; Lethal Dose 50; Mediating; Medicine; Migraine; Molecular; Motor Neurons; Mus; Muscle; Neurologic; Neuromuscular Junction; Neurons; Neurotoxins; Neurotransmitters; Oral; Paralysed; Pathogenesis; Peptide Hydrolases; Poisoning; Prevention; Process; Proteins; Resolution; Role; Serotyping; Specificity; Staging; Structure; Techniques; Testing; Therapeutic; Toxicology; Toxin; Transportation; Work; X-Ray Crystallography; base; clinical application; clinical efficacy; design; improved; insight; man; molecular mass; novel; novel strategies; novel therapeutic intervention; novel therapeutics; premature; prevent; progenitor; receptor binding; small molecule; success; urologic; weapons

DESCRIPTION (provided by applicant): Botulinum neurotoxins (BoNTs) are among the most poisonous substances known to man, with a 50% lethal dose (LD50) of 1 ng/kg in mice. BoNTs therefore represent a major bioterrorist threat (Arnon et al., 2001; Gill, 1982). Paradoxically, BoNT-containing medicines and cosmetics, such as Botox(R), Dysport(R), Xeomin(R), CBTXA(R), Myobloc(R) and NeuroBloc(R), have been used with great success to treat a variety of neurological, otolaryngological, ophthalmological, urological, dermatological and gastrointestinal disorders (Jankovic, 2004; Truong and Jost, 2006). In October 2010, FDA approved Botox(R) to treat chronic migraine. Both the toxic and therapeutic functions of BoNTs rely on a common mechanism to enter neurons, cleave proteins that mediate exocytosis of key neurotransmitters, and subsequently paralyze the affected muscles. BoNTs are produced by Clostridium botulinum as large progenitor toxin complexes (PTCs) that include auxiliary clostridial proteins known as neurotoxin-associated proteins (NAPs) (Montecucco and Schiavo, 1995). Clinical formulations are also composed of BoNT PTCs. Accidental BoNT poisoning mainly occurs through oral ingestion of tainted food products. NAPs are thought to protect BoNTs against the hostile environment of the gastrointestinal (GI) tract, and to mediate toxin transport across the epithelial cell barriers, the first step of intoxication. However the underlying molecular mechanisms that control these processes are poorly understood. The goal of this proposal is to elucidate the structure and function of BoNT PTCs, including the mechanism by which NAPs protect BoNTs, the regulatory mechanism underlying PTC assembly, and the structural basis by which NAPs regulate the interaction between BoNTs and host cells. The focus of this proposal is on the serotype A of BoNT (BoNT/A), because it is a major concern for bioterrorism and is the most commonly used medicine among all BoNT serotypes. We will use a combination of techniques, including X-ray crystallography, together with biochemistry, biophysics, cell biology, toxicology and bioinformatics. If successful, the proposed wok will guide the design of novel therapeutics for the treatment and/or prevention of botulism. Our work may also provide new insights into the activity and side effects of drugs such as Botox(R) and Dysport(R), which may help improve their clinical efficacy and suggest novel clinical applications.

描述(申请人提供)：肉毒杆菌神经毒素(BoNTs)是人类已知的最有毒的物质之一，对小鼠的半数致死剂量(LD50)为1 ng/kg。因此，BoNTs是一个重大的生物恐怖主义威胁(Arnon等人，2001；Gill，1982)。矛盾的是，含有BONT的药物和化妆品，如肉毒杆菌(R)、DySPORT(R)、Xeomin(R)、CBTXA(R)、Myobloc(R)和NeuroBloc(R)，已经被成功地用于治疗各种神经、耳鼻喉科、眼科、泌尿科、皮肤科和胃肠道疾病(Jankovic，2004；Truong and Jost，2006)。2010年10月，FDA批准肉毒杆菌(R)用于治疗慢性偏头痛。BoNTs的毒性和治疗功能都依赖于一种共同的机制进入神经元，裂解介导关键神经递质胞吐的蛋白质，然后瘫痪受影响的肌肉。BoNTs是由肉毒杆菌作为大的前体毒素复合体(PTCs)产生的，其中包括称为神经毒素相关蛋白(NAP)的辅助梭状芽胞杆菌蛋白(Montecucco和Schiavo，1995)。临床制剂也由BONT PTCs组成。意外的BONT中毒主要是通过口服受污染的食品发生的。NAP被认为可以保护BoNTs免受胃肠道(GI)恶劣环境的侵袭，并介导毒素通过上皮细胞屏障的运输，这是中毒的第一步。然而，控制这些过程的潜在分子机制却知之甚少。这项建议的目的是阐明BONT PTCs的结构和功能，包括NAPs保护BoNTs的机制，PTC组装的调控机制，以及NAPs调控BoNTs与宿主细胞之间相互作用的结构基础。这项建议的重点是A型BONT(BONT/A)，因为它是生物恐怖主义的一个主要问题，也是所有BONT血清型中最常用的药物。我们将使用包括X射线结晶学在内的多种技术，以及生物化学、生物物理学、细胞生物学、毒理学和生物信息学。如果成功，建议的锅将指导设计治疗和/或预防肉毒杆菌中毒的新疗法。我们的工作还可能为肉毒杆菌(R)和DySPORT(R)等药物的活性和副作用提供新的见解，这可能有助于提高它们的临床疗效，并提出新的临床应用。