在灵长类动物中,对热点动机的驱动使PRDM9基因参与介质重组
Simon Myers1, Rory Bowden, Afidalina Tumian
1Department of Statistics, Oxford University, 1 South Parks Road, Oxford OX1 3TG, UK. myers@stats.ox.ac.uk
Science (New York, N.Y.)
|January 2, 2010
概括
人类和黑猩猩的重组热点因特定的DNA动机而有所不同. 蛋白质PRDM9结合了这种基因,解释了物种特异性介质重组和快速进化变化的差异.
科学领域:
- 遗传学 是一个遗传学.
- 进化生物学 进化生物学
- 基因组学就是基因组学.
背景情况:
- 众所周知,人类和黑猩猩之间有所不同,即基因交叉聚焦的梅奥斯基重组热点.
- 一个特定的13个基对DNA基因因与人类重组热点的很大一部分有关.
研究的目的:
- 为了研究黑猩猩中已知的人类重组热点图案的功能差异.
- 确定人类和黑猩猩之间的重组热点差异背后的分子机制.
- 探索PRDM9蛋白在调解物种特异性重组模式中的作用.
主要方法:
- 对比基因组学分析以确定重组热点位置的差异.
- 功能性测试,以测试这两种物种中13个基对动机的活性.
- 蛋白质-DNA结合实验,以评估PRDM9和动机之间的相互作用.
- 分析PRDM9的进化变化及其与热点活动的相关性.
主要成果:
- 在人类热点中活跃的13个基对动机在黑猩猩中是非功能性的,在人类血统中正在经历负面选择.
- 有证据表明,指蛋白PRDM9与这种基因结合.
- 在PRDM9的序列变化与人类和黑猩猩之间的热点位置观察到的差异密切相关.
- PRDM9在基因组修饰 (H3K4三甲基化) 中的作用表明热点调节的保存机制.
结论:
- PRDM9是推动人类和黑猩猩重组热点分歧的关键因素.
- 这些发现表明,由PRDM9.9调节的重组热点存在于保存的真核生物机制中.
- 在PRDM9中的快速进化变化引发了关于塑造重组模式的进化力量的问题.
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