蛋白质的可用性和进化的速度
1enter for Computational Genetics and Biological Modeling, Department of Biological Sciences, Stanford University, California, USA. aehirsch@stanford.edu
Nature
|June 29, 2001
概括
蛋白质的可用性,或蛋白质对一个生物有多重要,与其进化速率相关. 这一发现在酵母和虫中得到证实,解释了以前发现这种关系的困难.
科学领域:
- 进化生物学是进化的生物学.
- 基因组学就是基因组学.
- 分子生物学分子生物学
背景情况:
- 假设蛋白质进化的速度随着蛋白质对生物体健康的重要性下降而增加.
- 这是因为不太重要的蛋白质在较弱的净化选择下,允许轻微有害的突变更快地积累.
- 之前的研究未能证实这种关系,有些研究显示基本基因与非基本基因之间的进化速率没有差异.
研究的目的:
- 为了研究蛋白质可用性和进化速率之间的关系,使用可用性的定量衡量.
- 为了确定蛋白质可用性是否影响进化速率,比简单的基本/非基本分类更准确.
- 评估蛋白质可用性和进化速率之间的关系的进化保存.
主要方法:
- 使用酵母中单基因缺失的高通量生长试验,对蛋白质可用性的定量评估.
- 通过对21个完全注释的基因组进行比较序列分析来估计进化速率.
- 统计分析以将蛋白质可用性与进化速率相关联.
主要成果:
- 在蛋白质可用性和进化速率之间发现了高度显著的正相关性.
- 这种关系比简单的基本与非基本二分法更为细微,解释了之前未能得到确认的尝试.
- 酵母中蛋白质可用性和进化速率之间的确定的关系在其他物种中得到保护和预测,例如线虫虫.
结论:
- 蛋白质可用性是进化速率的重要预测因素.
- 量化测量可用性揭示了蛋白质功能重要性和进化速度之间的关系.
- 这项研究协调了以前相互矛盾的发现,并为理解蛋白质进化提供了更准确的模型.
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