通道CORA的形态组合揭示了通道封闭的结构基础
Satchal K Erramilli1, Kamil Nosol1, Krzysztof Pietrzak-Lichwa1,2
1Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637.
概括
冠状腺管道调节 prokaryotes 中的的流入. 结构研究揭示了由水平控制的结构合集,将通道不对称性与细胞平衡门联系起来.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 分子生物物理学 分子生物物理学
背景情况:
- 冠状腺酶 (CORA) 是 prokaryotes 中的主要流入途径.
- 对于细胞生理和生物化学是必不可少的.
- 细胞内功能由细胞内依赖的负反循环调节,涉及子单元不对称.
研究的目的:
- 为了阐明CORA子单元不对称性和通道激活之间的联系.
- 了解CORA中依赖调节的结构基础.
- 为了建立一个框架,使在原核细胞的恒温.
主要方法:
- 单粒子冷电子显微镜 (cryo-EM) 解决了16个CORA结构.
- 纳米盘中CORA的复制.
- 利用特定于形状的合成抗体来稳定形状状态.
主要成果:
- 科拉存在于一组形态合奏的集合中.
- 整体种群大小与细胞内的度相反相关.
- 确定了多种多样的孔状结构 (收缩和扩张),表明了一系列功能状态.
- 通过静电网络将细胞质域中的不对称结构转换与透途径的变化联系起来.
结论:
- 科拉门被一系列的形态状态所控制.
- 细胞质域中的不对称性与孔状结构变化相结合.
- 这些发现为理解原生体平衡提供了一个框架.
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