进化容量作为复杂基因网络的一般特征
1Department of Biological Sciences, Stanford University, Stanford, California 94305-5020, USA.
Nature
|August 2, 2003
概括
大多数基因可以作为进化电容器,缓冲遗传变异并加速适应. 这种缓冲效应与Hsp90不同,不需要环境变化.
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.
- 分子生物学分子生物学
背景情况:
- 一个进化电容缓冲基因型变异,隐藏它,直到电容失败.
- 热冲击蛋白90 (Hsp90) 是一种已知的进化电容,抑制表型变异,并在受损时释放.
- Hsp90的功能受到环境压力的影响,它对发育有性作用.
研究的目的:
- 调查进化电容是否仅限于Hsp90或其他基因是否也可以充当电容器.
- 探索超出Hsp90.0.的进化电容的机制和范围.
- 为了确定基因中的功能丧失突变是否加速了适应.
主要方法:
- 复杂基因网络的数值模拟.
- 来自酵母单基因删除菌株的基因组规模表达数据的分析.
主要成果:
- 大多数,如果不是所有的基因,在功能性受损时可以显示表型变异.
- 功能丧失突变的可用性加速了对新表型的适应.
- 这种适应加速不需要环境依赖的突变.
结论:
- 一个广泛的进化电容类可能存在于Hsp90.0之外.
- 这些电容器补充Hsp90的系统性,环境诱导的影响.
- 了解这些电容器可以揭示适应机制的新见解.
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