有证据表明,无性繁殖或基因交换的bdelloid rotifers的进化是没有性繁殖或基因交换的
1Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|May 20, 2000
概括
一个独特的动物群体Bdelloid rotifers可能已经在数百万年内没有发生性繁殖的过程中进化. 遗传分析显示,它们的基因组缺乏类似的序列,支持这种长期无性进化假说.
科学领域:
- 动物学 动物学
- 进化生物学 进化生物学
- 遗传学 是一个遗传学.
背景情况:
- 班级Bdelloidea代表了最大的已知metazoan分类,没有雄性,雌性和半体.
- 这种独特的繁殖特征长期以来一直暗示着这些生物体可能有义务无性繁殖的可能性.
研究的目的:
- 为了分子测试这种假设,bdelloid rotifers已经进化没有性繁殖或基因交换数百万年.
- 调查基因组签名,表明长期缺少半变和遗传重组.
主要方法:
- 来自四种不同的bdelloid rotifers的基因组DNA测序.
- 生物信息分析用于检测在个体基因组内存在或缺少非常相似的哈普洛型对.
- 核酸序列的比较分析,以确定古老的血统分歧.
主要成果:
- 分析的Bdelloid rotifer基因组始终缺乏非常相似的核酸序列的对.
- 这些基因组含有高度分歧的序列代表,表明古代的血统分离.
- 有证据表明,这些血统在bdelloids的主要辐射之前已经分离,这可能标志着性繁殖的停止.
结论:
- 基因组数据强烈支持了bdelloid rotifers长期无性进化的假设.
- 没有相似的单个类型和古代不同的血统的存在提供了令人信服的证据,反对最近或正在进行的遗传交换.
- 这项研究为完全无性繁殖的生物体的进化途径提供了重要的见解.
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