追溯现代周等离子体结合蛋白的演化过程
Florian Michel1, Sergio Romero-Romero1, Birte Höcker1
1Department of Biochemistry, University of Bayreuth, Bayreuth, Germany.
Protein science : a publication of the Protein Society
|October 3, 2023
概括
研究人员将核糖结合蛋白 (RBP) 分成两半,证明这些半部分可以重新形成一个功能性蛋白质. 这支持了现代周等离子体结合蛋白 (PBPs) 从单一的祖先基因重复事件进化而来的假设.
科学领域:
- 蛋白质的进化是如何发生的
- 结构生物学是结构生物学.
- 分子进化的分子进化.
背景情况:
- 现代的多域蛋白质表现出多样化的结构和功能.
- 周等离子体结合蛋白 (PBPs) 是通过基因复制和融合研究蛋白质多样化的模型系统.
- PBPs的双叶结构表明,它们的进化起源来自单一的祖先基因.
研究的目的:
- 为了调查PBPs起源于单个祖先基因重复和融合事件的进化假设.
- 重建一个单叶PBP祖先的结构和功能等效.
- 用糖结合蛋白 (RBP) 作为模型来建模进化过程.
主要方法:
- 将核糖结合蛋白 (RBP) 分解成其组成的叶片.
- 孤立的RBP叶片的折叠,稳定性和结合功能的表征.
- 在RBP叶片的体外和细胞内异构化.
- 进行X射线晶体学以确定RBP异构体的结构.
主要成果:
- 孤立的RBP叶片是折叠良好的单体,但缺乏结合功能,并表现出降低的热稳定性.
- 两个RBP叶片在体外和细胞内很容易形成异构聚物.
- 异构体的X射线结构密切模仿了本地RBP结构.
- 在异体聚合物中,结合激素的结合功能完全恢复,其亲和力与原始RBP相当.
结论:
- 一个单一的祖先基因的复制可以产生稳定,功能性的PBP类折叠.
- 这项研究提供了关于复杂蛋白质结构从更简单的组成部分演变的见解.
- 这些发现支持PBP进化的基因复制和融合模型.
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