一个DARPin促进了肉毒神经毒素A1行动的更快开始
Oneda Leka1, Yufan Wu1, Giulia Zanetti2
1Laboratory of Biomolecular Research, Division of Biology, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland.
Nature communications
|December 18, 2023
概括
设计的安基林重复蛋白 (DARPins) 用于研究肉毒神经毒素A1 (BoNT/A1). 一种特定的DARPin,DARPin-F5,在体外抑制BoNT/A1,但增强其在细胞中的活性,表明治疗潜力.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- 神经科学是一个神经科学.
背景情况:
- 肉毒神经毒素 (BoNTs) 是具有治疗用途的强毒素.
- 了解BoNT的结构和功能对于开发向抑制剂和应用至关重要.
- 设计的安基林重复蛋白 (DARPins) 为蛋白质工程和分子探测提供了一个多功能平台.
研究的目的:
- 描述DARPins作为研究肉毒神经毒素A1 (BoNT/A1) 结构和功能的工具.
- 确定和描述一个新的 BoNT/A1.1.的DARPin抑制剂.
- 阐明已识别的DARPin.的抑制机制和亚型特异性.
主要方法:
- 设计安基林重复蛋白 (DARPins) 的蛋白质工程和表征.
- 试验室试验评估BoNT/A1酶活性和基质裂解抑制.
- 进行X射线晶体学以确定DARPin-BoNT相互作用的结构基础.
- 基于细胞的测试使用初级神经元和肌肉组织来评估在生理上下文中的BoNT/A1活动.
主要成果:
- 在体外鉴定DARPin-F5,它是BoNT/A1 SNAP25基质裂变的特定抑制剂.
- X射线结晶学显示,DARPin-F5与基质结合区域结合,阻断活性.
- DARPin-F5表现出亚型特异性,抑制BoNT/A1,但不抑制BoNT/A3.
- BoNT/A1 Glu-171对于DARPin-F5相互作用至关重要;对Asp的突变取消了抑制.
- 在初级神经元和肌肉中,DARPin-F5通过促进毒素转位来意外地增强BoNT/A1活动.
结论:
- DARPin-F5是体外BoNT/A1的强效和特异性抑制剂,提供了对毒素基质相互作用的见解.
- 这项研究强调了DARPin-F5.5在体外抑制和体内增强BoNT/A1活性之间的二分法.
- 这些发现表明BoNT/A1调制对于需要快速开始和持续作用的疗法有潜在的应用.
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