重建了形核糖核糖酶超级家族的进化史
T M Jermann1, J G Opitz, J Stackhouse
1Department of Chemistry, ETH Zürich, Switzerland.
Nature
|March 2, 1995
概括
研究人员使用精益求精重建了古代蛋白质序列. 古代核糖核酶 (RNases) 的活性增加,这表明消化性RNases是从非消化性祖先进化而来的.
科学领域:
- 进化生物学是进化的生物学.
- 分子进化的分子进化.
- 生物化学 生物化学
背景情况:
- 蛋白质进化可以通过从现存的亲属中重建祖先序列来研究.
- 节是一种通过尽量减少进化变化来推断祖先序列的方法.
- 核糖酶 (RNases) 是参与RNA代谢的酶,具有不同的功能.
研究的目的:
- 为了重建和表征古老的RNase蛋白序列在形动物血统内.
- 研究RNase功能的进化变化及其与生理适应的相关性.
- 评估在重建可信的古老蛋白质序列时,的有效性.
主要方法:
- 用一种以钱为基础的方法重建13个古老的RNase序列.
- 重建的古代RNase蛋白质的实验室合成和生物化学表征.
- 对双链RNA的催化活性进行比较分析.
主要成果:
- 重建的古代RNase序列被发现是可信的,基于它们的特性.
- 对双链RNA的催化活性增加了五倍,这在祖先的骨干RNase中观察到.
- 这种功能转变与动物消化在类动物中出现的出现有关.
结论:
- 帕西蒙尼是一种可行的方法来重建功能性古代蛋白质.
- 形人消化RNase的演化可能涉及从非消化祖先形式的过渡.
- 进化蛋白重建提供了对生理功能适应的见解.
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