广泛的基因组采样提高了动物生命树的分辨率
Casey W Dunn1, Andreas Hejnol, David Q Matus
1Kewalo Marine Laboratory, PBRC, University of Hawaii, 41 Ahui Street, Honolulu, Hawaii 96813, USA. casey_dunn@brown.edu
Nature
|March 7, 2008
概括
新的分子数据解决了深层动物的进化关系,证实了像Ecdysozoa和Lophotrochozoa这样的主要类. 这项研究澄清了天虫的位置,并支持了新的假设,包括虫作为最早的动物.
科学领域:
- * 动物进化生物学
- * 分子遗传学分子遗传学
- * 基因组学 是一个学科.
背景情况:
- * 传统的动物进化树受到分子数据的挑战,提出了像Ecdysozoa和Lophotrochozoa这样的新类.
- * 解决深层动物关系对于理解角色演变至关重要,但通常受到有限的数据和对深层节点的低支持的阻碍.
- * 遗传学方法很有前途,但需要在各种动物群中提供更广泛的数据覆盖.
研究的目的:
- *从广泛的动物类群中生成新的表达序列标签 (EST) 数据,以改善深层进化关系的解析.
- * 测试和完善现有关于动物类遗传的假设,包括软体动物的单一性和关节动物的姐妹群.
- * 调查螺旋裂变的进化起源和ctenophores的遗传学位置.
主要方法:
- * 测序了来自29个动物物种的39.9 Mb的表达序列标签 (ESTs) 在21个族群中.
- *将新的EST数据与现有的序列数据集成,用于全面的遗传学分析.
- * 应用族群基因组学方法来分析大型的组合数据集.
主要成果:
- * 加强了主要的分类群,如Protostomia,Ecdysozoa和Lophotrochozoa.
- *明确解决长期存在的争议,特别是将天虫作为关节动物的姊妹群,而不是迟行动物.
- * 强烈的分子支持软体动物的单一性和新的假设,包括一个有软体动物作为姐妹的类动物-尼默特人-足动物类,以及类动物作为最早的分离动物.
结论:
- * 该研究为关键动物类提供了强有力的分子证据,并解决了关键的遗传学不确定性.
- * 关于动物关系的新假设,包括ctenophores的基本位置,得到了强烈的支持.
- * 遗传学数据显著提升了我们对早期动物进化的理解,只剩下很少的反抗性血统.
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