一个疏水的锁固分子复合体
Georg K A Hochberg1, Yang Liu2, Erik G Marklund3
1Department of Ecology and Evolution, University of Chicago, Chicago, IL, USA.
Nature
|December 10, 2020
概括
许多蛋白质复合物由于"恐水性突变"而存在. 这种机制巩固了分子组合,即使它们的多元化没有明显的功能优势,也使得未组合的形式变得不稳定.
科学领域:
- 分子生物学
- 进化生物学
- 结构生物信息学
背景情况:
- 大多数蛋白质的功能是多个子单元的复合体.
- 蛋白质复合体的进化持久性通常归因于多元化的功能优势的选择.
- 然而,许多复合体缺乏可归因于组装的已知功能.
研究的目的:
- 研究蛋白质复合物的进化固的替代机制.
- 测试一种假设,即一种疏水性突变可以稳定复合体,
- 探索蛋白质稳定性和溶剂暴露在维持分子组合中的作用.
主要方法:
- 对类固醇激素受体进行的祖先蛋白重建和生物化学测试.
- 蛋白界面和突变倾向的结构生物信息学分析.
- 数以百计的多元家族的数据库分析.
主要成果:
- 由于暴露于溶剂时稳定性和聚合性降低,在类固醇激素受体中保留了古老的疏水界面,尽管缺乏可辨的功能.
- 一种普遍的突变偏差有利于在多重体接口中的埋藏位置的疏水替代,这对单体有害.
- 大多数分析的多元家族都显示出长期的疏水性固.
结论:
- 一个疏水性突变系统地驱动分子复合体的固.
- 这种机制解释了许多蛋白质复合物的持久性,即使它们的组合在功能上是无偿的.
- 由疏水性相互作用驱动的蛋白质复合体稳定性可以取代进化持久性的功能优势的需要.
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