自然选择和jingwei的起源,在Drosophila中的一个模拟处理的功能基因
1Section of Genetics, University of California, Davis 95616.
Science (New York, N.Y.)
|April 2, 1993
概括
在Drosophila中,一个处理过的基因,以前是一个伪基因,进化成一个名为jingwei的新功能基因. 这个基因的起源涉及从另一个基因捕获DNA,证明了自然选择在新基因进化中的作用.
科学领域:
- 进化生物学是进化的生物学.
- 分子遗传学 分子遗传学
- 基因组学就是基因组学.
背景情况:
- 新基因的起源是进化的基本过程.
- 了解基因起源需要检查分子机制和种群动态.
- 一个经过处理的Drosophila酒精脱酶 (Adh) 基因,最初被认为是一种伪基因,为研究新基因形成提供了一个独特的模型.
研究的目的:
- 研究涉及新功能基因起源的分子事件和种群动态.
- 通过捕获不相关的DNA序列来形成的嵌合基因的进化轨迹.
- 确定自然选择在新基因的出现和随后的进化中的作用.
主要方法:
- 处理的Adh基因的序列分析及其集成到一个新的遗传位置.
- 基因表达模式的比较,在新奇的仿真基因和其母基因Adh基因之间.
- 评估新基因的分子进化速率.
主要成果:
- 一个经过处理的Adh信使RNA序列被纳入了一个新的功能基因,称为jingwei,通过从一个无关基因中捕获上游的外子和内子.
- 新的仿真基因jingwei与其母基因adh相比,呈现出不同的表达模式.
- 在jingwei基因和最初的Adh基因之间,分子进化的速度有所不同.
- 有证据表明,自然选择在jingwei基因的起源和进化中发挥了作用.
结论:
- 这项研究表明,通过外子捕获和化学基因的形成,新基因的诞生有一个合理的途径.
- 京伟基因作为一个案例研究,以了解分子创新和自然选择在塑造基因组中的相互作用.
- 新的功能基因可以从以前非功能性的遗传元素中通过重组和调节产生.
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