对于bdelloid rotifer Adineta vaga中的ameiotic进化的基因组证据
Jean-François Flot1, Boris Hespeels, Xiang Li
1University of Namur, Department of Biology, URBE, Laboratory of Evolutionary Genetics and Ecology, 5000 Namur, Belgium. jean-francois.flot@ds.mpg.de
Nature
|July 23, 2013
概括
微观的动物,挑战进化论,坚持无性生活数百万年. 它们独特的基因组结构与常规的半变异不相容,揭示了新的进化策略.
科学领域:
- 进化生物学是进化的生物学.
- 基因组学就是基因组学.
- 动物世界 动物世界
背景情况:
- 性繁殖的丧失通常是动物进化的死胡同.
- 布德洛伊德是微观无脊椎动物,在数百万年里显然是无性繁殖的.
- 贝德洛伊德动物中缺少变和雄性生殖器官,挑战了已建立的进化原理.
研究的目的:
- 为了研究bdelloid rotifer Adineta vaga. 的基因组结构.
- 了解使bdelloids长期无性繁殖的遗传机制.
- 探索bdelloid无性繁殖的进化影响.
主要方法:
- 的基因组测序 Adineta vaga.
- 对比的基因组分析.
- 基因家族的识别和基因组重组.
主要成果:
- 阿迪内塔·瓦加 (Adineta vaga) 的基因组是四重体,具有重新排列的等位基因区域,与介质配对不相容.
- 丰富的基因转换证据表明,存在一种限制有害突变的机制,而无需介质变化.
- 确定了与抗氧化,碳水化合物代谢和转子子体防御相关的扩大基因家族.
- 大约8%的基因来自非甲状动物,可能是通过横向基因转移获得的.
结论:
- 阿迪内塔·瓦加独特的基因组结构提供了长期无性繁殖的机制,挑战了基因动物生存的性需求.
- 基因转换和水平基因转移似乎是bdelloid rotifers的关键进化策略.
- 这项研究为性别的进化意义和生命形式的适应性提供了新的见解.
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