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高分辨率的酵母乙烯结构表明了乙烯丝通过阴离子变硬的分子机制
Xiao-Ping Xu1, Wenxiang Cao2, Mark F Swift1
1Scintillon Institute, 6868 Nancy Ridge Drive, San Diego, CA, 92121, USA.
Communications chemistry
|July 30, 2024
概括
离子通过桥接子单元来化actin丝,模仿酵母中的脊椎动物actin特性. 这一发现揭示了如何调节actin线程力学和蛋白质相互作用.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 结构生物学 结构生物学
背景情况:
- 动蛋白丝组合和机械性质调节对于真核细胞功能至关重要.
- 脊椎动物的行为体具有E167残留物,形成盐桥,有助于丝的刚性,而酵母行为体具有A167,从而产生更灵活的丝.
- 在位置167的酵母活性蛋白从氨酸转变为谷氨酸 (A167E),恢复了与脊椎动物活性蛋白类似的依赖盐的刚性.
研究的目的:
- 为了阐明Saccharomyces cerevisiaeactin纤维的改变硬度的结构基础.
- 为了识别负责控制actin导线刚度的导线相关离子.
- 了解在调节活性丝的机械性质和蛋白质相互作用中的作用.
主要方法:
- 开发了一种优化的冷电子显微镜 (cryo-EM) 工作流程,用于近原子分辨率的结构确定.
- 确定了野生类型和A167E突变型Saccharomyces cerevisiae的高分辨率结构.
- 分析了先前发表的和新确定的高分辨率脊椎动物的行动蛋白结构.
主要成果:
- 在A167E酵母活性蛋白和脊椎动物活性蛋白中,在A167E残留物167附近确定了一个与线索相关的阴离子的潜在结合点.
- 对动素结构的分析揭示了与167.7残留物附近离子结合一致的峰值.
- 证明可以桥接actin子单元,使细丝变硬,并对DNase-I结合循环产生全性影响.
结论:
- 离子通过直接桥接子单元,在酸纤维硬化中发挥关键作用.
- 的结合对DNase-I结合循环具有全性影响,调节丝的刚性和蛋白质相互作用.
- 这项研究揭示了介导的丝丝丝硬化在不同物种的保存机制.
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