类的基因组演变
Adam M Session1,2, Yoshinobu Uno3, Taejoon Kwon4,5
1University of California, Berkeley, Department of Molecular and Cell Biology and Center for Integrative Genomics, Life Sciences Addition #3200, Berkeley, California 94720-3200, USA.
Nature
|October 21, 2016
概括
Xenopus laevis的基因组揭示了它来自3400万年前分离的两个原始物种. 这种基因复制会影响基因保留和不对称的亚基因组进化.
科学领域:
- 比较基因组学
- 进化生物学
- 两动物遗传学
背景情况:
- 整基因组复制是进化创新的重要驱动力.
- 非洲爪 (Xenopus laevis) 是一种具有复杂进化历史的四足类物种.
- 了解四体物种的基因组结构和进化轨迹对于破译基因组进化至关重要.
研究的目的:
- 调查Xenopus laevis四粒体的起源和进化后果.
- 为了比较二倍体的 Xenopus laevis 与其二倍体的 Xenopus tropicalis 的基因组.
- 描述X. laevis的亚基因组组成和进化动态.
主要方法:
- 对Xenopus laevis和Xenopus tropicalis进行基因组测序.
- 生物信息分析以将X. laevis基因组分为同源子基因组.
- 识别和分析可转移的元素和伪基因以估计分离和多化时间.
- 对基因保留,蛋白质功能,基因表达和序列保存进行比较分析.
主要成果:
- Xenopus laevis 的基因组被分为两个不同的同质基因组,由独特的可转移元素家族标记.
- 预计祖先物种在约3400万年前分离 (Ma) 并且在约17-18万年前全化.
- 超过56%的基因被保留在同质拷贝中,保留率与蛋白质功能,基因表达和侧面序列保护相关.
- 亚基因组的不对称进化,其中一个保留了祖先状态,另一个经历了显著的基因损失,重新排列和减少表达.
结论:
- 这项研究阐明了Xenopus laevis的全四类起源,并提供了关于其形成时间和机制的见解.
- 在X. laevis的基因复制导致了基因差异保留和不对称的亚基因组进化,塑造了其当前的遗传格局.
- 这些发现有助于更广泛地了解多体脊椎动物的基因组进化和全基因组重复事件的功能后果.
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