大规模的形态动态控制 H5N1 流感聚合酶 PB2 结合进口蛋白
Elise Delaforge1,2,3, Sigrid Milles1,2,3, Guillaume Bouvignies1,2,3
1Univ. Grenoble Alpes , Institut de Biologie Structurale (IBS), F-38044 Grenoble, France.
Journal of the American Chemical Society
|October 2, 2015
概括
流感PB2蛋白质
科学领域:
- 分子生物学
- 病毒学
- 结构生物学
背景情况:
- 流感ARNA聚合酶复合体需要PA,PB1和PB2子单元.
- 在聚合酶组装之前,PB2蛋白被导入核中.
- PB2 (627-NLS) 的C端形成了一个不清晰的进口因子结合机制的异构体.
研究的目的:
- 阐明627-NLS对重要素的亲和性的分子基础.
- 为了研究627-NLS的形状动态.
- 了解形状的灵活性如何促进进口约束.
主要方法:
- 溶液状态核磁共振 (NMR)
- 微角中子散射
- 小角度X射线散射 (SAXS)
- 福斯特共振能量转移 (FRET)
- 化学交换和转移 (CEST)
主要成果:
- 627-NLS存在于关闭和开放状态之间的温度依赖的动态平衡.
- 封闭状态由盐桥稳定,在开放状态下断裂.
- 只有开放状态与importin α结合,这表明了形状选择.
- 绑定到importin α需要动态采样.
结论:
- 627-NLS的内在形状灵活性对于进口蛋白结合至关重要.
- 温度会影响功能和非功能状态之间的平衡.
- 从动态组合中进行符合性选择可实现有效的进口识别.
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