一种突变积累试验揭示了基因表达快速演变的广泛能力
Scott A Rifkin1, David Houle, Junhyong Kim
1Department of Ecology and Evolutionary Biology, Yale University, PO Box 208106, New Haven, Connecticut 06520-8106, USA.
Nature
|November 11, 2005
概括
突变通过创造新的基因表达变异来推动生物多样性. 这项研究表明,虽然突变可以产生丰富的基因表达变化,但自然变异相对受到限制,特别是在发育过程中.
科学领域:
- 进化生物学是进化的生物学.
- 遗传学 是一个遗传学.
- 发育生物学是发展生物学.
背景情况:
- 突变是生物多样性的主要来源.
- 基因表达对于将遗传信息转化为发育变化至关重要.
研究的目的:
- 为了估计基因表达因突变而产生的新变异的速率.
- 调查发育背景如何影响基因表达的进化.
主要方法:
- 在12个Drosophila melanogaster系中测量整个基因组中的转录丰度.
- 线条最初是相同的,并累积突变超过200代.
- 分析的重点是转型的开始.
主要成果:
- 在39%的基因组中发现了统计学上显著的突变变异.
- 基因变异性在发育期间上调时降低,在下调时增加.
- 突变变异和环境变异之间的强烈相关性表明有道化潜力.
结论:
- 基因表达进化并不严格遵循中立模型.
- 自发突变可以产生大量的基因表达变异,但自然变异受到限制.
- 发育背景在塑造基因表达进化的过程中起着重要作用.
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