剂量敏感性和酵母菌中基因家族的演变
Balázs Papp1, Csaba Pál, Laurence D Hurst
1Department of Biology and Biochemistry, University of Bath, Bath, Somerset BA2 7AY, UK.
Nature
|July 11, 2003
概括
蛋白质复合体子单元失衡会降低身体健康,支持平衡假说. 这表明主导来自生理学,而不是选择,并解释了为什么大型基因家族避免复杂.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 进化生物学 进化生物学
背景情况:
- 蛋白质-蛋白质复合体对于细胞功能至关重要.
- 亚单位度的不平衡会扰乱复杂的静脉测量和功能.
- 平衡假设认为,这种不平衡是有害的.
研究的目的:
- 为了测试酵母 (Saccharomyces cerevisiae) 中平衡假设的预测.
- 为了研究蛋白质复杂子单元共同调节,基因重复和健康之间的关系.
- 探索平衡假设对理解主导地位和基因家族进化的影响.
主要方法:
- 对酵母中的基因表达数据和蛋白质-蛋白质相互作用网络的分析.
- 评估蛋白质复杂子单元的表达不足和过度表达对身体健康的影响.
- 检查转录协调精度与子单元失衡之间的相关性.
- 调查大型基因家族中蛋白质复合体成员的流行情况.
主要成果:
- 发现蛋白质复杂子单元的低表达和过度表达都会降低酵母的健康状况.
- 副单元的转录性共同调节的更高准确性与减少的负面适应性影响相关.
- 蛋白质子单元的单基因重复与负面的健康后果有关.
- 大基因家族的成员在蛋白质复合体中明显不足.
结论:
- 这些发现强烈支持平衡假设,表明蛋白质复合体子单元的静态度失衡是有害的.
- 主导性可能是生理和代谢约束的副产品,而不是掩盖突变的适应性特征.
- 平衡假设为理解子单元静态度,主导性和基因家族进化提供了一个统一的框架.
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