A multi-locus analysis of phylogenetic relationships within grass subfamily Pooideae (Poaceae) inferred from sequences of nuclear single copy gene regions compared with plastid DNA.
A multi-locus analysis of phylogenetic relationships within grass subfamily Pooideae (Poaceae) inferred from sequences of nuclear single copy gene regions compared with plastid DNA.
复制标题
DOI：
10.1016/j.ympev.2015.03.010
复制
发表时间：
2015-06
影响因子：
4.1
通讯作者：
Anne Hochbach;J. Schneider;M. Röser
中科院分区：
文献类型：
--
作者：
Anne Hochbach;J. Schneider;M. Röser
为了研究禾本科早熟禾亚科内的系统发育关系，我们使用一个质体 DNA (cpDNA) 标记（matK 基因 - 3′trnK 外显子）和首次四个核单拷贝基因位点，研究了涵盖所有已识别部落的约 50 个分类群。生成了来自跨外显子 8-13 和 17-19 的核基因拓扑异构酶 6 (Topo6) 的两个部分、编码质体乙酰辅酶 A 羧化酶 (Acc1) 的外显子 9-13 和光敏色素 B (PhyB) 的部分外显子 1 的 DNA 序列信息。使用最大简约法、最大似然法和贝叶斯方法评估个体和核组合数据。所有的系统发育结果都表明 Brachyelytrum 和 Nardeae 部落是该亚科内最早的分化谱系。 “核心”早熟禾科（Hordeeae 和 Aveneae/Poeae 部落复合体）以及 Brachypodieae、Meliceae 和 Stipeae 部落（PhyB 除外）的单系也得到了强烈支持。在一些分析中，喙草族Diarreneae 和Duthieeae 族并不是单系的。然而，组合核DNA（nDNA）树产生了最高分辨率和最好的部落划分，并为部落提供了以下进化假设：Brachyelytrum、Nardeae、Duthieeae、Meliceae、Stipeae、Diarreneae、Brachypodieae和“核心”Pooideae。在各个数据集中，从 Topo6 外显子 8-13 获得的系统发育树显示了最有趣的结果。例如，毛里塔蛇蛇行草（Ampelodesmos mauritanicus）和乳头三角蛇（Trikeraia pappiformis）的一些克隆序列的不同位置可能表明这些针刺类群的杂交起源。
To investigate phylogenetic relationships within the grass subfamily Pooideae we studied about 50 taxa covering all recognized tribes, using one plastid DNA (cpDNA) marker (matK gene–3′trnK exon) and for the first time four nuclear single copy gene loci. DNA sequence information from two parts of the nuclear genes topoisomerase 6 (Topo6) spanning the exons 8–13 and 17–19, the exons 9–13 encoding plastid acetyl-CoA-carboxylase (Acc1) and the partial exon 1 of phytochrome B (PhyB) were generated. Individual and nuclear combined data were evaluated using maximum parsimony, maximum likelihood and Bayesian methods. All of the phylogenetic results showBrachyelytrumand the tribe Nardeae as earliest diverging lineages within the subfamily. The ‘core’ Pooideae (Hordeeae and the Aveneae/Poeae tribe complex) are also strongly supported, as well as the monophyly of the tribes Brachypodieae, Meliceae and Stipeae (exceptPhyB). The beak grass tribe Diarrheneae and the tribe Duthieeae are not monophyletic in some of the analyses. However, the combined nuclear DNA (nDNA) tree yields the highest resolution and the best delimitation of the tribes, and provides the following evolutionary hypothesis for the tribes:Brachyelytrum, Nardeae, Duthieeae, Meliceae, Stipeae, Diarrheneae, Brachypodieae and the ‘core’ Pooideae. Within the individual datasets, the phylogenetic trees obtained fromTopo6exon 8–13 shows the most interesting results. The divergent positions of some clone sequences ofAmpelodesmos mauritanicusandTrikeraia pappiformis, for instance, may indicate a hybrid origin of these stipoid taxa.