在基质识别之前,分子拥挤驱动活跃的Pin1进入与内源性蛋白质的非特异性复合体
Laura M Luh1, Robert Hänsel, Frank Löhr
1Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University , Frankfurt, 60438, Germany.
Journal of the American Chemical Society
|August 24, 2013
概括
细胞拥挤通过弱吸引相互作用影响蛋白质行为. 像Ficoll 70这样的分子拥挤剂不能准确地模仿这些细胞内相互作用.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
背景情况:
- 大分子拥挤显著影响细胞环境,影响蛋白质动态,结构和活性.
- 拥挤在体内改变蛋白质功能的确切机制仍在争论中.
- 了解这些影响对于理解细胞过程至关重要.
研究的目的:
- 为了研究分子拥挤在Xenopus laevis卵细胞中的基-基异构酶Pin1上的作用.
- 在拥挤的细胞环境中区分影响蛋白质行为的特定和非特定相互作用.
- 评估合成拥挤剂在复制原生细胞内条件中的适用性.
主要方法:
- 细胞内核磁共振 (NMR) 光谱被用来研究Pin1.1.
- 在本地Xenopus laevis卵子和拥挤的卵子提取物中进行了实验.
- 分析了酸化对Pin1相互作用的影响.
主要成果:
- 活性Pin1在基质结合之前与细胞内蛋白进行弱吸引相互作用.
- Pin1的基质识别部位调解了特定和非特定的吸引力相互作用.
- 酸化Pin1的WW域取消了基质识别和内源蛋白相互作用.
- 像Ficoll 70这样的合成拥挤剂无法复制体内发现的必不可少的弱吸引相互作用.
结论:
- 这项研究支持麦肯基关于中性球状蛋白在拥挤的环境中形成复合体的假设.
- 非特定的弱吸引相互作用是细胞内环境的关键组成部分.
- 合成拥挤剂不足以准确模拟复杂的本地细胞环境.
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