Phylogeny of the families Zoothamniidae and Epistylididae (Protozoa: Ciliophora: Peritrichia) based on analyses of three rRNA-coding regions
Phylogeny of the families Zoothamniidae and Epistylididae (Protozoa: Ciliophora: Peritrichia) based on analyses of three rRNA-coding regions
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基于三个 rRNA 编码区分析的 Zoothamniidae 和 Episylididae 科（原生动物：纤毛纲：Peritrichia）的系统发育
DOI：
10.1016/j.ympev.2017.09.023
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发表时间：
2018
影响因子：
4.1
通讯作者：
Ji Daode
中科院分区：
文献类型：
--
作者：
Zhuang Yuan;Clamp John C.;Yi Zhenzhen;Ji Daode
缘毛类是世界性分布的纤毛虫的主要类群，在许多生境中起着重要作用。使用三个基因的信息，这提供了比单基因分析更强大的解释，一些围毛虫的家族内遗传进行了研究。将67个新序列（SSU rDNA、ITS 1 -5. 8 S-ITS 2和LSU rDNA）与GenBank中已有序列进行比对，以推测虫科和虫尾科的系统发育关系。结果表明：（1）附柱虫科是多系的，由两个分支组成，作为围毛类冠部分支的一部分巢居在虫科内部（涡藻目）和第三个是一部分的基础分支peritrichs（2）Epistylis elongatafalls在Zoothelium的一个分支内，而不是与同源物;（3）Zoothamnopsis属可能是并系的，由三个不同的分支组成，Myoschiston属和Zoothamnopsis属与Zoothamnopsis种混杂。从这些结果可以推断出以下进化假说：（1）动杆菌属的收缩柄是近形的。（2）Myoschiston、Zoothamnopsis和Epistylididae的第二分支是由Zoothamnopsis形态型演化而来的。(3)Epistylididae的第I分支，主要是殖民形式，似乎从来没有进化出任何种类的spasmoneme，可能代表了peritrichs的祖先形态。
Peritrichs are a major group of ciliates with worldwide distribution, and they play important roles in many habitats. Intrafamilial phylogeny of some peritrichs was investigated using information from three genes, which provided more robust interpretations than single-gene analyses. Sixty-seven new sequences including SSU rDNA, ITS1-5.8S-ITS2 and LSU rDNA were aligned with available sequences in GenBank to infer phylogenetic relationships within the families Zoothamniidae and Epistylididae. Results reveal the following relationships: (1) Epistylididae is polyphyletic, consisting of two clades that nest within the Zoothamniidae as part of the crown clade of peritrichs (order Vorticellida) and a third one that is part of the basal clade of peritrichs (order Opercularida); (2)Epistylis elongatafalls within one of the clades ofZoothamniumrather than with congeners; (3)Zoothamniumis probably paraphyletic, consisting of three divergent clades, with the generaMyoschistonandZoothamnopsisintermingled with species ofZoothamnium. The following evolutionary hypotheses can be inferred from these results: (1) the contractile stalk ofZoothamniumis plesiomorphic. (2)Myoschiston, Zoothamnopsisand clade II of Epistylididae are derived from theZoothamniummorphotype by partial or incomplete development of the spasmoneme that forms the contractile center of the stalk around which the rigid cortex is secreted. (3) Clade I of the Epistylididae, which are primarily colonial forms that appear never to have evolved a spasmoneme of any sort, may represent the ancestral morphotype of peritrichs.