The phylogenetic positions of three basal-hexapod groups (Protura, Diplura, and Collembola) based on ribosomal RNA gene sequences
The phylogenetic positions of three basal-hexapod groups (Protura, Diplura, and Collembola) based on ribosomal RNA gene sequences
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DOI：
10.1093/molbev/msi148
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发表时间：
2005-07-01
影响因子：
10.7
通讯作者：
Yin, WY
中科院分区：
文献类型：
--
作者：
Luan, YX;Mallatt, JM;Yin, WY
这项研究将完整的18S与部分28S核糖体RNA基因序列（总共相似，总计2,000 nt），以研究基础六足的关系。测序了十种Protura，12种，十二只，十个Collembola（代表这三个进化枝的所有亚组），以及5种真实的昆虫和其他8种节肢动物，它们用作外部组。用最大的简约，最大似然，贝叶斯分析和对LogDet转换距离的最小进化分析来构建树木。所有方法都为Protura Plus Plus Diplura（Nonoculata）和单次文凭的单元提供了强有力的支持。参数启动分析分析表明，我们的数据与以前的假设（p <0.01）不一致，该假设将Protura与Collembola（Ellipura）（Ellipura）连接在一起，那就是文术是真正的昆虫或二屈菌的姐妹，并且认为Collembola不是六脚架。也就是说，我们的数据与在大多数分析条件下与“ protura + diptura”弱分组的六脚架一致。作为上述结论的警告，这些序列显示了整个分类单元的核苷酸频率的非平稳性，因此外武器和Proturans的富含CG的序列可能会人为地分组。但是，LogDet方法支持该组的事实减少了这一可能性。在核苷酸频率固定的基础六足类中，通常会回收传统的分类亚组：即，在Protura，eosentomata和acerentomata（但sinentomata不是单属体）；在Collembola中，节肢动物，poduromorpha和entomobryomorpha（但Symphypleona是多形的）；在文凭中，最完整的数据集（> 2,100 nt）显示了campodoidea和japygoidea的单性别，大多数方法与Japygoidea结合在一起。
This study combined complete 18S with partial 28S ribosomal RNA gene sequences (similar to 2,000 nt in total) to investigate the relations of basal hexapods. Ten species of Protura, 12 of Diplura, and 10 of Collembola (representing all subgroups of these three clades) were sequenced, along with 5 true insects and 8 other arthropods, which served as out-groups. Trees were constructed with maximum parsimony, maximum likelihood, Bayesian analysis, and minimum-evolution analysis of LogDet-transformed distances. All methods yielded strong support for a clade of Protura plus Diplura, here named Nonoculata, and for monophyly of the Diplura. Parametric-bootstrapping analysis showed our data to be inconsistent with previous hypotheses (P < 0.01) that joined Protura with Collembola (Ellipura), that said Diplura are sister to true insects or are diphyletic, and that said Collembola are not hexapods. That is, our data are consistent with hexapod monophyly and Collembola grouped weakly with "Protura + Diplura" under most analytical conditions. As a caveat to the above conclusions, the sequences showed nonstationarity of nucleotide frequencies across taxa, so the CG-rich sequences of the diplurans and proturans may have grouped together artifactually; however, the fact that the LogDet method supported this group lessens this possibility. Within the basal hexapod groups, where nucleotide frequencies were stationary, traditional taxonomic subgroups generally were recovered: i.e., within Protura, the Eosentomata and Acerentomata (but Sinentomata was not monophyletic); within Collembola, the Arthropleona, Poduromorpha, and Entomobryomorpha (but Symphypleona was polyphyletic); and in Diplura, the most complete data set (> 2,100 nt) showed monophyly of Campodeoidea and of Japygoidea, and most methods united Projapygoidea with Japygoidea.