在人类和黑猩猩的基因组和转录组中,进化的并行模式
Philipp Khaitovich1, Ines Hellmann, Wolfgang Enard
1Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, D-04103 Leipzig, Germany.
Science (New York, N.Y.)
|September 6, 2005
概括
通过比较人类和黑猩猩的基因组,可以发现基因表达和蛋白质序列在各个组织中的类似模式. 大脑基因显示的差异较小,而肝脏基因显示的差异较大,这表明不同的进化约束.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 进行比较基因组学.
背景情况:
- 黑猩猩基因组的测序为了解人类基因组进化提供了宝贵的资源.
- 对人类和黑猩猩基因组的比较分析可以阐明遗传差异及其功能后果.
研究的目的:
- 为了比较人类和黑猩猩之间的基因表达水平和蛋白质编码序列.
- 通过同源基因对基因进化进行组织特异性差异的研究.
主要方法:
- 来自人类和黑猩猩组织 (大脑,心脏,肝脏,脏,丸) 的基因表达数据的比较分析.
- 分析蛋白质编码序列以确定进化变化和选择性压力.
主要成果:
- 基因表达和序列分歧模式在人类和黑猩猩之间在各个组织中都非常相似.
- 有选择性约束的梯度存在,大脑显示的差异最小,肝脏显示的差异最大.
- 在更多的组织中表达的基因比在较少的组织中表达的基因差异较小.
- 丸中的X染色体基因显示出对序列和表达变化的积极选择的证据.
- 大脑中的基因在人类血统中积累了更多的变化,而不是在黑猩猩血统中.
结论:
- 人类和黑猩猩基因组进化表现出受组织特异性选择性压力影响的保存模式.
- 通常支持负选择的中性进化,但对于特定的基因组 (例如丸中的X染色体基因) 表明正选择.
- 大脑基因进化,虽然显示出较少的分歧,但具有独特的血统特异性变化模式,有利于人类血统.
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