在封闭状态下探测相隔聚合物的微环境中的不均质扩散
Marjan Shayegan1, Radin Tahvildari1, Kimberly Metera1
1Department of Physics , McGill University , Montreal , Quebec H3A 2T8 , Canada.
Journal of the American Chemical Society
|April 25, 2019
概括
生物分子凝聚物对细胞功能至关重要,在体内使用受限显微镜进行了研究. 研究人员观察到异常扩散,
科学领域:
- 细胞生物学
- 生物物理
- 生物化学
背景情况:
- 通过液相分离形成的生物分子凝聚物越来越被认为是细胞的重要组成部分.
- 它们的结构组织和生物物理性质对于它们的功能至关重要,但人们对它们的理解仍然很少,尤其是在体内尺度上.
- 现有的体外研究通常使用比细胞内发现的更多的凝结物.
研究的目的:
- 研究生物分子凝聚物的结构组织和生物物理特性,在生理上相关的,类似于体内的尺寸.
- 探索封闭的冷凝物中的探测粒子的动态,并将它们与冷凝物大小和组成联系起来.
主要方法:
- 使用封闭显微镜可视化和控制生物分子凝聚物的大小.
- 创建了模仿细胞环境的特定限制长度尺度.
- 使用探针粒子扩散测量来分析内部动力学.
主要成果:
- 在封闭的凝聚物中观察到探测颗粒的异常扩散.
- 在PEG/dextran和核糖蛋白 (RNP) 凝聚物中检测到异质动态.
- 提出了一个跳跃扩散机制来解释非高斯动态.
- 发现富含德克斯的凝聚物中的探针粒子扩散,但不是RNP凝聚物,取决于凝聚物大小.
结论:
- 封闭显微镜可以在生物相关的尺度上研究生物分子凝聚物.
- 异常扩散和异质动力学表明凝结体内部有复杂的内部组织和运输机制.
- 凝析体大小可以影响内部动力学,特别是在某些组合物中,如富含德克斯的系统.
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