...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>BMC Genomics >Tunicate mitogenomics and phylogenetics: peculiarities of the Herdmania momus mitochondrial genome and support for the new chordate phylogeny
【24h】

Tunicate mitogenomics and phylogenetics: peculiarities of the Herdmania momus mitochondrial genome and support for the new chordate phylogeny

机译：外皮线粒体基因组学和系统发育学：Herdmania momus线粒体基因组的特殊性和对新的碳酸盐系统发育的支持

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Background Tunicates represent a key metazoan group as the sister-group of vertebrates within chordates. The six complete mitochondrial genomes available so far for tunicates have revealed distinctive features. Extensive gene rearrangements and particularly high evolutionary rates have been evidenced with regard to other chordates. This peculiar evolutionary dynamics has hampered the reconstruction of tunicate phylogenetic relationships within chordates based on mitogenomic data. Results In order to further understand the atypical evolutionary dynamics of the mitochondrial genome of tunicates, we determined the complete sequence of the solitary ascidian Herdmania momus. This genome from a stolidobranch ascidian presents the typical tunicate gene content with 13 protein-coding genes, 2 rRNAs and 24 tRNAs which are all encoded on the same strand. However, it also presents a novel gene arrangement, highlighting the extreme plasticity of gene order observed in tunicate mitochondrial genomes. Probabilistic phylogenetic inferences were conducted on the concatenation of the 13 mitochondrial protein-coding genes from representatives of major metazoan phyla. We show that whereas standard homogeneous amino acid models support an artefactual sister position of tunicates relative to all other bilaterians, the CAT and CAT+BP site- and time-heterogeneous mixture models place tunicates as the sister-group of vertebrates within monophyletic chordates. Moreover, the reference phylogeny indicates that tunicate mitochondrial genomes have experienced a drastic acceleration in their evolutionary rate that equally affects protein-coding and ribosomal-RNA genes. Conclusion This is the first mitogenomic study supporting the new chordate phylogeny revealed by recent phylogenomic analyses. It illustrates the beneficial effects of an increased taxon sampling coupled with the use of more realistic amino acid substitution models for the reconstruction of animal phylogeny.
机译：背景外衣代表了重要的后生动物群，作为脊索动物中脊椎动物的姐妹群。迄今为止，可供被膜处理的六个完整的线粒体基因组已显示出鲜明的特征。关于其他脊索动物，已经证明了广泛的基因重排以及特别高的进化速率。这种独特的进化动力学阻碍了基于线粒体基因组数据的线粒体内被膜系统发育关系的重建。结果为了进一步了解被膜的线粒体基因组的非典型进化动力学，我们确定了孤本的Herdmania momus的完整序列。这个来自花枝as子海鞘的基因组呈现出典型的被膜基因含量，其中包含13个蛋白质编码基因，2个rRNA和24个tRNA，它们均在同一条链上编码。但是，它也提供了一种新颖的基因排列，突出了在被膜线粒体基因组中观察到的基因顺序的极端可塑性。从主要后生门的代表的13个线粒体蛋白编码基因的串联进行概率系统发生推断。我们显示，虽然标准的均质氨基酸模型支持被膜相对于所有其他bilaterians的人工假体位置，但CAT和CAT + BP的位点和时间异质混合模型将被膜作为单亲脊索类脊椎动物的姊妹组。此外，参考系统发生学表明，被膜线粒体基因组的进化速度急剧加快，这同样影响蛋白质编码和核糖体RNA基因。结论这是第一个支持最近的系统生物学分析揭示新的碳酸盐系统发育的线粒体基因组学研究。它说明了增加分类单元采样的有益效果，并结合使用更现实的氨基酸替代模型来重建动物系统发育。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号