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Z染色体和人类X染色体通过扩张和基因获取的融合进化
Daniel W Bellott1, Helen Skaletsky, Tatyana Pyntikova
1Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, Massachusetts 02142, USA.
Nature
|July 13, 2010
概括
鸟类和哺乳动物的性别染色体,就像Z和X染色体一样,进化趋同. 他们独立地获得了丸表达的基因,并扩大了基因间区域,挑战了关于它们进化的先前假设.
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:
- 鸟类 (ZZ雄,ZW雌) 和哺乳动物 (XY雄,XX雌) 的性别确定涉及不同的性别染色体.
- 在两性中存在的Z和X染色体,被认为与它们的自体源相差极小.
- 仅在一个性别中存在的W和Y染色体被认为是性染色体进化的主要地点.
研究的目的:
- 为了研究Z染色体的进化轨迹,并将其与人类X染色体进行比较.
- 挑战Z和X染色体与自体细胞差异很小的假设.
- 为了确定鸟类和哺乳动物的性别染色体之间的共同特征和进化模式.
主要方法:
- 的Z染色体的测序. 的Z染色体的测序.
- 对的Z染色体和人类X染色体序列的全面比较分析.
- 对基因密度,基因重复和基因间区域扩张的生物信息分析.
主要成果:
- 的Z染色体的基因密度低于自体和含有重复的丸表达基因.
- 的Z染色体和人类的X染色体独立地从不同的祖先基因组区域进化.
- Z和X染色体都表现出融合进化,其特点是丸表达基因的放大和扩展的基因间区域,使它们与自动体区分开来.
结论:
- Z和X染色体的进化涉及到相似特征的收购,尽管不同的异性恋系统.
- 鸟类和哺乳动物的性别染色体进化是由性别特异性染色体中的基因损失和两性共同的染色体中的基因增益/扩张的特征.
- Z和X染色体在从自体体分离后获得了独特的特征,表明了超越简单分离的活跃进化过程.
相关概念视频
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