数字生物体中的基因组复杂性,强度和遗传相互作用
R E Lenski1, C Ofria, T C Collier
1Center for Microbial Ecology, Michigan State University, East Lansing 48824, USA. lenski@pilot.msu.edu
Nature
|August 24, 1999
概括
数字生物体,进化的计算机程序,显示复杂的生物体对突变更强大. 突变相互作用是常见的,并提高适应性,这是遗传系统的一般特征.
科学领域:
- * 计算生物学 * 计算生物学
- * 进化计算是一种进化计算.
- * 人工生命 * 人工生命
背景情况:
- 数字生物 (自我复制,突变和适应的计算机程序) 为研究超越有机生命的进化原理提供了一个模型.
- *研究简单和复杂的数字生物之间的遗传结构差异可以揭示进化强度和突变效应的概括性见解.
研究的目的:
- * 为了比较简单的数字生物体 (选择复制) 与复杂的数字生物体 (选择加速复制的代谢奖励) 的遗传强度.
- *分析单个和多个突变对这些数字生物体适应性的影响.
- * 确定不同数字生物类的突变之间的相互作用的流行率和影响.
主要方法:
- *生成两个类型的数字生物:简单的 (复制专注) 和复杂的 (增强新陈代谢).
- * 将数百万个单个和多个突变引入数字生物体.
- *测量生物体的适应性,以评估突变及其相互作用的影响.
主要成果:
- *复杂的数字生物与简单的生物相比,对单个突变的平均影响具有更大的稳定性.
- *突变之间的相互作用是频繁的,通常会导致比乘法效应预测的更高的适应性.
- *这些突变相互作用在复杂的数字生物中尤为显著.
结论:
- * 突变相互作用是遗传系统中普遍存在的特征,在数字和生物生物体中观察到.
- *一个生物体的遗传系统的复杂性会影响其强度和突变的影响.
- *研究结果支持突变相互作用的普遍性,作为进化和适应的一个基本方面.
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