醇衍生物与正位的结合会导致无脊椎动物Cys-loop受体的形状变化
Steven De Gieter1,2, Casey I Gallagher3, Eveline Wijckmans3
1Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium.
eLife
|July 3, 2023
概括
研究人员研究了来自极端虫Alvinella pompejana的孤儿受体Alpo4. 冷-EM结构揭示了其连接物结合部位和离子孔的独特特征,为Cys-loop受体多样性提供了洞察力.
科学领域:
- 结构生物学是结构生物学.
- 神经科学是一个神经科学.
- 进化生物学是进化的生物学.
背景情况:
- 环受体 (pentameric联离子通道) 对于神经传递至关重要.
- 无脊椎动物的Cys循环受体,特别是nAChR类基因,比脊椎动物的对应物了解得更少.
- 无脊椎动物中nAChR类基因的基因扩张表明了多种功能和进化途径.
研究的目的:
- 为了研究孤儿Cys-loop受体Alpo4的分子机制,来自极端爱好虫Alvinella pompejana.
- 了解无脊椎动物中神经传递的结构基础和Cys-loop受体的演变.
主要方法:
- 序列分析以确定Alpo4与已知的nACh受体的进化关系.
- 低温电子显微镜 (cryo-EM) 来解决Alpo4受体的结构.
- 对连接体结合和离子孔特性进行分析.
主要成果:
- 确定了lophotrochozoan nACh-like受体Alpo4的冷-EM结构,其中一个CHAPS分子与orthosteric部位结合.
- CHAPS结合会诱导形状变化,包括循环C延伸和域间的四元扭曲.
- 在联体结合部位 (B环中保存的Trp) 和离子孔 (氨酸环收缩) 中发现了独特的特征.
结论:
- 这项研究提供了对无脊椎动物孤儿受体Alpo4.4的第一个结构洞察.
- 独特的结构特征表明了新的功能性质和潜在的自我连接体相互作用.
- 这些发现为了解Alpo4功能和开发特定调制器提供了结构基础.
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