德乌特罗斯托姆系谱揭示了单体带动物和新的系Xenoturbellidalida
Sarah J Bourlat1, Thorhildur Juliusdottir, Christopher J Lowe
1Department of Biology, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK.
Nature
|October 20, 2006
概括
解读了deuterostome的原型,支持了Olfactores (耳带动物,脊椎动物) 和Ambulacraria (耳带动物,皮动物). 鉴定出Xenoturbella是一个独特的族群,Xenoturbellida,解决了deuterostome进化关系.
科学领域:
- * 进化生物学和动物类学.
- *比较基因组学和分子系统学.
背景情况:
- * 双体包括脊椎动物和无脊椎动物,如半脊椎动物,皮动物和Xenoturbella.
- * 之前的研究表明,带动物是脊椎动物的最亲密的亲属,挑战了传统观点,并提出了带动物的副属性.
研究的目的:
- * 解决所有主要的双胞胎体组之间的进化关系.
- * 为了研究Xenoturbella在deuterostomes中的遗传位置.
- * 为了澄清状动物的单类或副类.
主要方法:
- * 组装了来自不同类别的双胞胎体的35,000多种同类氨基酸的大规模对齐.
- *对Xenoturbella的线粒体基因组进行测序.
- *使用核和线粒体数据的综合基因分析.
主要成果:
- * 确认了Olfactores (带动物和脊椎动物) 和Ambulacraria (半带动物和皮动物) 的单一性.
- * 拒绝了头带动物与皮动物的拟议分组,支持带动物单基.
- *将Xenoturbella置于Ambulacraria的姊妹群中,将其确立为一个新的族群,Xenoturbellida.
结论:
- *这项研究支持已建立的基层,并驳斥了带状类类的假设.
- *Xenoturbella代表了一种独立的进化血统,使已知Deuterostome类的数量增加到四个.
- *为理解deuterostome进化和起源提供了一个强大的框架.
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