翻译的表观遗传调节揭示了隐藏的遗传变异,产生复杂的特征
Heather L True1, Ilana Berlin, Susan L Lindquist
1Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA.
Nature
|August 18, 2004
概括
酵母[PSI(+) ]使细胞能够通过阅读无意义的编码子,在各种条件下生存. 这种表观遗传因素促进了复杂特征的获得和稳定,影响了进化.
科学领域:
- 分子生物学分子生物学
- 进化生物学 进化生物学
- 遗传学 是一个遗传学.
背景情况:
- 现型可塑性和隐藏的遗传变异影响特征进化,但分子机制仍然不清楚.
- 酵母子[PSI(+) ]是Sup35p的一种形状变体,是一种保存的基于蛋白质的遗传元素.
- [PSI(+) ]是通过母体传播的,影响细胞存活和表型表达.
研究的目的:
- 研究酵母 [PSI(+) ] 影响表型可塑性和特征演变的分子机制.
- 为了确定[PSI(+) ]介导的无意义编码子读透是否是观察到的表型多样性的基础.
- 探索[PSI(+) ]如何有助于复杂特征的获得和稳定.
主要方法:
- 具有和没有[PSI(+) ]子的酵母菌株的分析.
- 检查跨不同遗传背景和生长条件的表型多样性.
- 作为一个分子机制,对[PSI(+) ]依赖的无意义编码子的读透的研究.
主要成果:
- 所有测试的特征都与[PSI(+) ]介导的无意义编码子的读透相关.
- 复杂的[PSI(+) ]依赖的表型经常通过遗传重组转化为独立于[PSI(+) 的稳定特征.
- [PSI(+) ] 在各种环境中提供了暂时的生存优势.
结论:
- 酵母 [PSI(+) ] 作为一种表观遗传因子,在全球范围内调节基因型-表型关系.
- [PSI(+) ]提供了一个快速获得复杂特征的机制,并促进它们的遗传同化.
- 这种表观遗传机制扩大了对表型可塑性和进化路径的理解,使其成为新的特征.
相关概念视频
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Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
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