Estimation of divergence times in cnidarian evolution based on mitochondrial protein-coding genes and the fossil record
Estimation of divergence times in cnidarian evolution based on mitochondrial protein-coding genes and the fossil record
复制标题
DOI：
10.1016/j.ympev.2011.10.008
复制
发表时间：
2012-01-01
影响因子：
4.1
通讯作者：
Won, Yong-Jin
中科院分区：
文献类型：
--
作者：
Park, Eunji;Hwang, Dae-Sik;Won, Yong-Jin
刺胞动物门是由非常多样的和生态上重要的分类群，如造礁珊瑚，并在后生动物进化中占据基础地位。这个门的起源和其现代类的最近共同祖先（MRCA）仍然是未知的，尽管分散的化石证据提供了一些关于这个主题的见解。在这里，我们调查的主要分类组的刺胞动物（27六珊瑚目，16珊瑚目，和5水母）的13个蛋白质编码基因的线粒体DNA序列的基础上的分子分歧时间。对于这项分析，完整的线粒体基因组的七个珊瑚和两个scyphozoan物种的新测序，并结合所有可用的有丝分裂基因组数据从基因库。五个可靠的化石日期被用来校准贝叶斯估计的分歧时间。分子证据表明，刺胞动物起源于7.41亿年前（Ma）（686-819的95%可信区域），主要类群在寒武纪（543 Ma）之前多样化。石珊瑚和石珊瑚可能起源于二叠纪-三叠纪大灭绝幸存者的辐射，这与它们的化石记录很好地吻合。(C)2011 Elsevier Inc. All rights reserved.
The phylum Cnidaria is comprised of remarkably diverse and ecologically significant taxa, such as the reef-forming corals, and occupies a basal position in metazoan evolution. The origin of this phylum and the most recent common ancestors (MRCAs) of its modern classes remain mostly unknown, although scattered fossil evidence provides some insights on this topic. Here, we investigate the molecular divergence times of the major taxonomic groups of Cnidaria (27 Hexacorallia, 16 Octocorallia, and 5 Medusozoa) on the basis of mitochondrial DNA sequences of 13 protein-coding genes. For this analysis, the complete mitochondrial genomes of seven octocoral and two scyphozoan species were newly sequenced and combined with all available mitogenomic data from GenBank. Five reliable fossil dates were used to calibrate the Bayesian estimates of divergence times. The molecular evidence suggests that cnidarians originated 741 million years ago (Ma) (95% credible region of 686-819), and the major taxa diversified prior to the Cambrian (543 Ma). The Octocorallia and Scleractinia may have originated from radiations of survivors of the Permian-Triassic mass extinction, which matches their fossil record well. (C) 2011 Elsevier Inc. All rights reserved.