Platyzoan paraphyly based on phylogenomic data supports a noncoelomate ancestry of spiralia.
Platyzoan paraphyly based on phylogenomic data supports a noncoelomate ancestry of spiralia.
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基于系统发育数据的扁形动物并系动物支持旋涡虫的非腔皮动物祖先
DOI：
10.1093/molbev/msu143
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发表时间：
2014
影响因子：
10.7
通讯作者：
Hankeln
中科院分区：
文献类型：
--
作者：
Struck;Wey-Fabrizius;Golombeck;Hering;Weigert;Bleidorn;Klebow;Iakovenko;Hausdorf;Petersen;Herlyn;Hankeln
根据分子数据，在双毛虫中已识别出三个主要分支：后口亚纲、蜕皮亚纲和螺旋纲。在Spiralia中，小型和简单组织的动物，如扁虫、胃毛和颌口动物最近被归类为扁形动物。然而，在各自的分子系统发育研究中，假定的扁平动物的代表性很低，无论是分类单元数量还是序列数据。此外，扁形动物类群中更高的替换率增加了一种可能性，即由于长分支的吸引，单系扁形动物是一种人工制品。为了克服这些问题，我们采用了系统基因组学的方法，从而大大增加了1)扁形动物内样本物种的数量和2)物种特定序列在多达82,162个氨基酸位置的数据集中的覆盖率。使用已建立的和新的度量(长分支得分)，我们将系统发育信号从诸如长分支吸引等误导效应中分离出来。在这样做的过程中，我们的系统基因组分析并没有恢复到鸭嘴兽的单一系统起源，相反，相对于其他螺旋虫，它似乎是同源的。扁形蠕虫和胃毛虫组成一个单门，我们称之为轮虫。除Gnathifera外，轮虫和所有其他螺旋虫代表一个单系群，我们将其命名为扁形纲。Platyzoan认为，螺目动物的最后一个共同祖先是一种简单的生物体，没有体腔、节段和复杂的脑结构，而更复杂的动物，如环节动物，是从这样一个简单组织的祖先进化而来的。这一结论与另一种进化方案相矛盾，该方案提出了比拉特里亚和斯皮拉尼亚的环节动物祖先和几个独立的次级退化事件。
Based on molecular data three major clades have been recognized within Bilateria: Deuterostomia, Ecdysozoa, and Spiralia. Within Spiralia, small-sized and simply organized animals such as flatworms, gastrotrichs, and gnathostomulids have recently been grouped together as Platyzoa. However, the representation of putative platyzoans was low in the respective molecular phylogenetic studies, in terms of both, taxon number and sequence data. Furthermore, increased substitution rates in platyzoan taxa raised the possibility that monophyletic Platyzoa represents an artifact due to long-branch attraction. In order to overcome such problems, we employed a phylogenomic approach, thereby substantially increasing 1) the number of sampled species within Platyzoa and 2) species-specific sequence coverage in data sets of up to 82,162 amino acid positions. Using established and new measures (long-branch score), we disentangled phylogenetic signal from misleading effects such as long-branch attraction. In doing so, our phylogenomic analyses did not recover a monophyletic origin of platyzoan taxa that, instead, appeared paraphyletic with respect to the other spiralians. Platyhelminthes and Gastrotricha formed a monophylum, which we name Rouphozoa. To the exclusion of Gnathifera, Rouphozoa and all other spiralians represent a monophyletic group, which we name Platytrochozoa. Platyzoan paraphyly suggests that the last common ancestor of Spiralia was a simple-bodied organism lacking coelomic cavities, segmentation, and complex brain structures, and that more complex animals such as annelids evolved from such a simply organized ancestor. This conclusion contradicts alternative evolutionary scenarios proposing an annelid-like ancestor of Bilateria and Spiralia and several independent events of secondary reduction.
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影响因子：
2.8
作者：
Heuer CM;Müller CH;Todt C;Loesel R
通讯作者：
Loesel R
影响因子：
3.4
作者：
Nesnidal MP;Helmkampf M;Meyer A;Witek A;Bruchhaus I;Ebersberger I;Hankeln T;Lieb B;Struck TH;Hausdorf B
通讯作者：
Hausdorf B
影响因子：
4.1
作者：
Kueck, Patrick;Struck, Torsten H.
通讯作者：
Struck, Torsten H.
影响因子：
4.1
作者：
Bernt, Matthias;Bleidorn, Christoph;Struck, Torsten H.
通讯作者：
Struck, Torsten H.
Plathelminthes 和 Plathelminthomorpha — 并系类群
DOI：
10.1111/j.1439-0469.1996.tb00808.x
发表时间：
2009
影响因子：
1.9
作者：
G. Haszprunar
通讯作者：
G. Haszprunar