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1.
Molecular analyses have been used recently to refine our knowledge of phylogenetic relationships within the ciliated protozoa
(phylum Ciliophora). A current Hennigian phylogeny of the orders in the class Colpodea, based on light and electron microscopic
analyses, makes three important assumptions with regard to apomorphic character states, namely, (1) that the kreyellid silver
line evolved early in colpodean phylogeny, separating bryometopids, such as Bryometopus, from all other colpodeans; (2) that the macro–micronuclear complex is an autapomorphy of the cyrtolophosidids, such as Platyophrya; and (3) that merotelokinetal stomatogenesis is an apomorphic character of colpodids, such as Colpoda, Bresslaua, and Pseudoplatyophrya. These predictions of relationships within the class Colpodea were investigated by determining the complete small subunit
rRNA gene sequences for the colpodid Bresslaua vorax, the grossglockneriid Pseudoplatyophrya nana, and the cyrtolophosidid Platyophrya vorax and a partial sequence for the bryometopid Bryometopus sphagni. These sequences were combined with the previously published complete SSrRNA sequences for the colpodid Colpoda inflata and the bursariomorphid Bursaria truncatella. The affiliations were assessed using both distance matrix and maximum-parsimony analyses. The tree topologies for the class
Colpodea were identical in all analyses, with bootstrap support for bifurcations always exceeding 60%. The results suggest
the following. (1) Since the clade including Bryometopus and its sister taxon, Bursaria, is never basal, the kreyellid silver-line system evolved later in colpodean phylogeny and does not separate bryometopids
from all other colpodeans. (2) Since Platyophrya is always the sister taxon to the other five genera, there is a fundamental phylogenetic significance for its macro–micronuclear
complex. (3) Since the colpodids, Colpoda, Bresslaua, and Pseudoplatyophrya, always group in one clade, merotelokinetal stomatogenesis appears to be a derived character state.
Received: 30 June 1998 / Accepted: 3 December 1998 相似文献
2.
SPENCER J. GREENWOOD MARTIN SCHLEGEL MITCHELL L. SOGIN DENIS H.LYNN 《The Journal of eukaryotic microbiology》1991,38(1):1-6
ABSTRACT The complete small subunit rRNA gene sequences of the heterotrich Blepharisma americanum and the colpodid Colpoda inflata were determined to be 1719 and 1786 nucleotides respectively. the phylogeny produced by comparisons with other ciliates indicated that C. inflata is allied more closely with the nassophoreans and oligohymenophoreans than the spirotrichs. This is consistent with the placement of the colpodids in the Class Copodea. Blepharisma americanum was not grouped with the hypotrichs but instead was placed as the earliest branching ciliate. the distinct separation of B. americanum supports the elevation to class status given the heterotrichs based on morphological characters. 相似文献
3.
Phylogeny of Trichomonads Inferred from Small-Subunit rRNA Sequences 总被引:13,自引:0,他引:13
JOHN GUNDERSON GREGORY HINKLE DETLEF LEIPE HILARY G. MORRISON SHAWN K. STICKEL DAVID A. ODELSON JOHN A. BREZNAK THOMAS A. NERAD MIKLOS MÜLLER MITCHELL L. SOGIN 《The Journal of eukaryotic microbiology》1995,42(4):411-415
ABSTRACT. Small subunit (16S-like) ribosomal RNA sequences were obtained from representatives of all four families constituting the order Trichomonadida. Comparative sequence analysis revealed that the Trichomonadida are a monophyletic lineage and a deep branch of the eukaryotic tree. Relative to other early divergent eukaryotic assemblages the branching pattern within the Trichomonadida is very shallow. This pattern suggests the Trichomonadida radiated recently, perhaps in conjunction with their animal hosts. From a morphological perspective the Devescovinidae and Calonymphidae are considered more derived than the Monocercomonadidae and Trichomonadidae. Molecular trees inferred by distance, parsimony and likelihood techniques consistently show the Devescovinidae and Calonymphidae are the earliest diverging lineages within the Trichomonadida, however bootstrap values do not strongly support a particular branching order. In an analysis of all known 16S-like ribosomal RNA sequences, the Trichomonadida share most recent common ancestry with unidentified protists from the hindgut of the termite Reticulitermes flavipes. The position of two putative free-living trichomonads in the tree is indicative of derivation from symbionts rather than direct descent from some free-living ancestral trichomonad. 相似文献
4.
将自测的中国狼蛛科Lycosidae4亚科6属26种和从GenBank中检索到的北美2种豹蛛的mtD-NA-16S rRNA序列进行比较;以漏斗蛛科1种蜘蛛作为外群,对碱基序列的组成和遗传距离进行了分析,采用Bayesian方法和最大简约法(MP)构建分子系统树。研究结果表明:16SrRNA基因的部分序列为340bp到360bp,A T含量平均为75%,存在较强的A T含量偏向性;序列共有157个碱基存在变异,其中79个简约信息位点。狼蛛科各属间的遗传距离介于0.026 ̄0.200之间。2种建树方法均表明:科内的属及属内的种优先聚在一起;水狼蛛属相对马蛛属是狼蛛科中较为原始的类群,分化较早;獾蛛属作为1个单系群与熊蛛属合为1个并系,属于狼蛛亚科。狼蛛科6属间的分子系统关系为(Pirata(Hippasa(Trochsa Arctosa(Pardosa Wadicosa))))。 相似文献
5.
JUN GONG THORSTEN STOECK ZHENZHEN YI MIAO MIAO QIANQIAN ZHANG DAVID McL. ROBERTS ALAN WARREN WEIBO SONG 《The Journal of eukaryotic microbiology》2009,56(4):339-347
ABSTRACT. The hypostome ciliates have been generally classified into two classes, Phyllopharyngea and Nassophorea. The status of Nassophorea and its relationship with Phyllopharyngea is one of the most controversial issues in ciliate systematics. Here we focus on the phylogenetic interrelationships of Nassophorea and Phyllopharyngea based on small subunit ribosomal RNA gene sequences. The three nassophorean subgroups, synhymeniids, microthoracids, and nassulids, each emerged as monophyletic, with synhymeniids as a sister group of Phyllopharyngea, and microthoracids as a sister of the synhymeniids+Phyllopharyngea clade in all phylogenies. The exact placement of the nassulids, however, remains uncertain. Following a detailed analysis of phenotypic characters, we hypothesize that: (1) the Phyllopharyngea could have evolved from synhymeniids, with the further development of their subkinetal microtubules as one of the major events; and (2) the development of monokinetid structures, as well as the reduction and specialization of the cyrtos and cortex, might have occurred during the diversifications of the microthoracids, synhymeniids, and Phyllopharyngea from a common ancestor. Expanding the class Phyllopharyngea to include the synhymeniids as a subclass, and designating a new subclass Subkinetalia n. subcl. for the group comprising cyrtophorians, chonotrichians, rhynchodians, and suctorians, are proposed. 相似文献
6.
7.
LIFANG LI WEIBO SONG ALAN WARREN MANN KYOON SHIN ZIGUI CHEN DAODE JI PING SUN 《The Journal of eukaryotic microbiology》2008,55(5):448-456
ABSTRACT. In order to re‐evaluate the systematics of sessilid peritrich ciliates, small subunit (SSU) rRNA gene sequences were determined for 12 species belonging to five genera: Vorticella, Pseudovorticella, Epicarchesium, Zoothamnium, and Zoothamnopsis. Phylogenetic trees were deduced using Bayesian inference, maximum parsimony, and maximum likelihood methods. The phylogenetic analyses suggest that (1) sessilids which have stalks with continuous myonemes that contract in a zig‐zag fashion form a separate clade from those which have stalks that contract independently and in a spiral fashion, supporting the separation of the family Zoothamniidae from the family Vorticellidae and (2) Epicarchesium and Pseudovorticella, both of which have reticulate silverline systems, are more closely related to each other than to other vorticellids, suggesting that differences in the silverline system (i.e. transverse vs. reticulate) may be the result of genuine evolutionary divergence among sessilid peritrichs. However, the newly sequenced Zoothamnopsis sinica, which has a reticulate silverline pattern, nests within the unresolved Zoothamnium species that have transverse silverline patterns. Thus, there were at least two evolutions of the reticulate silverline pattern character state from a plesiomorphic transverse state in the peritrichid ciliates. The molecular work demonstrates the genus Zoothamnium to be paraphyletic in relation to morphological studies, and suggests that Astylozoon, Opisthonecta, and Vorticella microstoma possibly share a SSU rRNA secondary structure in the helix E10‐1 region. 相似文献
8.
由于云斑蛛属Cyrtophora蜘蛛所织的网形态上较为特殊,所以该属分类地位长期以来有异议.为从分子水平探讨该属系统发生地位,本文对相关的11种蜘蛛线粒体12S rRNA基因和核18S rRNA基因部分序列进行了测定.基于12S rRNA和18S rRNA基因序列联合数据进行的分子系统发生分析结果表明云斑蛛属属于园蛛科,该结果提示在园蛛总科分类实践中以蛛网形态特征为分类依据时要慎重考虑其可靠性. 相似文献
9.
鹳形目鸟类的传统分类一直存在分歧,而近期的分子系统学研究大多只用单个基因,其结论的可信度需要进一步验证.本文通过核c-mos基因和线粒体12S rRNA基因序列分别和合并分析,采用分子系统学方法探讨了鹳形目6科12种鸟类的系统发生关系.文中测出鹳形目鸟类6种核c-mos基因的片断序列,结合来自Genebank的其他种类的c-mos和12S rRNA基因序列,分别经Clustal W软件对位排列后,以原鸡为外类群用最大似然法、邻接法和最大简约法建立系统树.系统树分析表明, 鹳形目6科之间的系统发生关系总结为:(鹭科,((鹮科,美洲鹫科),(鹳科,(鲸头鹳科,锤头鹳科)))).鹭科7个属之间的系统发生关系总结为:(麻(开鸟)属(夜鹭属(池鹭属(苍鹭属(中白鹭属(白鹭属,大白鹭属)))))).分别基于两个单基因的系统树有一定差异,而基于合并数据的系统树支持率和分辨率都高于基于单基因的系统树,表明使用在遗传上相对独立的分子数据合并建立系统树有较高的可信度和分辨率,是一种更好的研究方法. 相似文献
10.
Phylogenetic relationships within the group of molting protostomes were reconstructed by comparing the sets of 18S and 28S rRNA gene sequences considered either separately or in combination. The reliability of reconstructions was estimated from the bootstrap indices for major phylogenetic tree nodes and from the degree of congruence of phylogenetic trees obtained by different methods. By either criterion, the phylogenetic trees reconstructed on the basis of both 18 and 28S rRNA gene sequences were better than those based on the 18S or 28S sequences alone. The results of reconstruction are consistent with the phylogenetic hypothesis classifying protostomes into two major clades: molting Ecdysozoa (Priapulida + Kinorhyncha, Nematoda + Nematomorpha, Onychophora + Tardigrada, Myriapoda + Chelicerata, and Crustacea + Hexapoda) and nonmolting Lophotrochozoa (Plathelminthes, Nemertini, Annelida, Mollusca, Echiura, and Sipuncula). Nematomorphs (Nematomorpha) do not belong to the clade Cephalorhyncha (Priapulida + Kinorhyncha). It is concluded that combined data on the 18S and 28S rRNA gene sequences provide a more reliable basis for phylogenetic inferences.__________Translated from Molekulyarnaya Biologiya, Vol. 39, No. 4, 2005, pp. 590–601.Original Russian Text Copyright © 2005 by Petrov, Vladychenskaya. 相似文献
11.
12.
To study the phylogenetic relationships of the macaques, five gene fragments were sequenced from 40 individuals of eight species:
Macaca mulatta, M. cyclopis, M. fascicularis, M. arctoides, M. assamensis, M. thibetana, M. silenus, and M. leonina. In addition, sequences of M. sylvanus were obtained from Genbank. A baboon was used as the outgroup. The phylogenetic trees were constructed using maximum-parsimony
and Bayesian methods. Because five gene fragments were from the mitochondrial genome and were inherited as a single entity
without recombination, we combined the five genes into a single analysis. The parsimony bootstrap proportions we obtained
were higher than those from earlier studies based on the combined mtDNA dataset. Excluding M. arctoides, our results are generally consistent with the classification of Delson (1980). Our phylogenetic analyses agree with earlier
studies suggesting that the mitochondrial lineages of M. arctoides share a close evolutionary relationship with the mitochondrial lineages of the fascicularis group of macaques (and M. fascicularis, specifically). M. mulatta (with respect to M. cyclopis), M. assamensis assamensis (with respect to M. thibetana), and M. leonina (with respect to M. silenus) are paraphyletic based on our analysis of mitochondrial genes. 相似文献
13.
络新妇亚科曾归入园蛛科,后改为属于肖蛸科,目前又升格为科级阶元。为对络新妇亚科的分类地位作进一步研究,测定了9种蜘蛛线粒体12SrRNA基因的部分序列;另外还从GenBank检索到17种蜘蛛的12SrRNA基因的的相应序列。基于12SrRNA基因序列进行的分子系统发生分析结果表明络新妇亚科即不属于园蛛科、也不属于肖蛸科,而是与肖蛸科或园蛛科均无直接关联的独立支系,这个结果证实了将络新妇亚科升格为科级阶元的有效性。 相似文献
14.
The Gobioninae are a group of morphologically and ecologically diverse Eurasian freshwater cyprinid fishes. The intergeneric
relationships of this group are unresolved and the possible monophyly of this subfamily remains to be established. We used
complete mitochondrial cytochrome b gene sequences from most genera within the gobionine group, in addition to a selection of cyprinid outgroups, to investigate
the possible monophyly of this group and resolve the interrelationships within the group. Our results support the monophyly
of the Gobioninae and identify four monophyletic groups within the subfamily; the Hemibarbus group, the Sarcocheilichthys group, the Gobio group, and the Pseudogobio group. The morphologically aberrant genera Gobiobotia, Xenophysogobio and Gobiocypris are included in the Gobioninae, with the latter a sister group of Gnathopogon. 相似文献
15.
16.
用mtDNA 12S rRNA序列变异检验鲤形目鱼类系统发育关系 总被引:9,自引:0,他引:9
通过对鲤形目鱼类5个科的代表类群的完整线粒体12S rRNA进行测序和分析,以检验目前的形态学假说。经序列比对后,有1000个位点,其中467个位点在茎区,533个在环区;有395个位点为变化位点,其中267个为系统发育信息位点。采用邻接法和最大简约法进行了系统发育分析,其结果支持鲤科鱼类成为一个单系群,非鲤科的鲤形目鱼类成为另一个单系群的观点,这与Siebert提出的假说相一致。鲤科鱼类包含3个主要的分支,即鱼丹系、鲤系和雅罗鱼系;但在非鲤科鲤形目鱼类中,其关系不能得到很好的解决,其中鳅科是复系,平鳍鳅科、条鳅亚科和花鳅亚科可能有较近的亲缘关系。 相似文献
17.
SUN YOUNG KIM EUN JIN YANG JUN GONG JOONG KI CHOI 《The Journal of eukaryotic microbiology》2010,57(6):460-467
ABSTRACT. The identification of Favella ehrenbergii, a marine planktonic ciliate, has largely been based on its lorica features. This approach is potentially problematic given the polymorphic lorica during this organism's life cycle. We isolated a population of F. ehrenbergii from the coastal waters of Incheon, Korea, and revealed its infraciliature using the protargol staining method. Phylogenetic analysis based on small subunit rRNA gene sequences was also performed. Results showed that this population possessed 16 collar membranelles (CM) and about 100 somatic kineties. These features are highly conserved, even in later dividers. As such, the number of CM and somatic kineties can be used as key characteristics for identification of Favella species. 相似文献
18.
Total DNA was extracted from 25 species (8 genera) of the subfamily Lamioideae sensu Erdtman (family Labiatae). Using rbcL-specific primers, the rbcL gene was amplified by polymerase chain reaction (PCR) and 1420 bp were sequenced directly, or after cloning. RbcL sequences were evaluated with character-state (maximum parsimony; PAUP) and distance methods (neighbour-joining; MEGA). In agreement with classical systematics all taxa studied cluster outside the Nepetoideae. The following clades are apparent: I - Westringia/Prostanthera, II - Ajuga/Teucrium and III - Scutellaria, Stachys, Lamium and Marrubium. Lamium album, L. amplexicaule and L. garganicum appear as a sister clade to Marrubium. Both share a common ancestor with a second Lamium clade (including L. purpureum, L. maculatum and L. galeobdolon). The phylogenetic relationships are discussed with regard to the systematic classification of the subfamilies Lamioideae and Nepetoideae (sensu Erdtman). 相似文献
19.
J. Zimmermann J. M. Gonzalez C. Saiz-Jimenez W. Ludwig 《Geomicrobiology journal》2013,30(7-8):379-388
Acidobacteria have been established as a novel and widespread bacterial phylum consistently detected during 16S rDNA-based molecular surveys. Recently, representatives of the phylum Acidobacteria were found to make up a large percentage of cloned sequences recovered from paleolithic paintings. The present study addresses the intraphylum diversity of Acidobacteria in Altamira Cave. In contrast to previous studies, we have focused on 23S rRNA-based phylogenetic analyses, exploiting the high information content of the 23S RNA gene. Comparison with existing studies was facilitated by the preparation of corresponding 16S rRNA clone libraries. Fourty-one distinct operational taxonomic units (OTU) could be identified. Of the eight described acidobacterial subgroups, five were represented in the cave; only subgroups 1, 2, and 8 were not found. Subgroup 4 was the group harbouring the highest number of OTUs. Various clusters that could not be assigned to any of the established subgroups, but were clearly grouped within the phylum and appeared to represent new taxa at elevated phylogenetic levels, were detected. Results from this study give a first insight into the enormous acidobacterial diversity existing in a single hypogean environment containing unique paleolithic paintings, the Altamira Cave. Novel taxa have been found within the phylum, suggesting a higher diversity of Acidobacteria than previously suspected even at a local scale. 相似文献
20.
SHAN GAO WEIBO SONG HONGWEI MA JOHN C. CLAMP ZHENZHEN YI KHALED A. S. AL‐RASHEID ZIGUI CHEN XIAOFENG LIN 《The Journal of eukaryotic microbiology》2008,55(6):562-566
ABSTRACT. The small subunit ribosomal RNA genes of nine species belonging to six genera of litostome ciliates, namely Amphileptus aeschtae, Chaenea teres, Chaenea vorax, Lacrymaria marina, Litonotus paracygnus, Loxophyllum sp.‐GD‐070419, Loxophyllum jini, Loxophyllum rostratum, and Phialina salinarum, were sequenced for the first time. Phylogenetic trees were constructed using different methods to assess the inter‐ and intra‐generic relationships of haptorians, of which Chaenea, Lacrymaria, Litonotus, and Phialina were analyzed for the first time based on molecular data. Monophyly of the order Pleurostomatida was strongly confirmed, and the two existing families of pleurostomatids, created on the basis of morphology, were confirmed by molecular evidence. Within the Pleurostomatida, Siroloxophyllum utriculariae occupied a well‐supported position basal to the Loxophyllum clade, supporting the separation of these genera from one another. Both the subclass Haptoria and the order Haptorida were partially unresolved, possibly paraphyletic assemblages of taxa in all analyses, creating doubts about the traditional placement of some haptorid taxa. The existing sequence of L. rostratum in GenBank (DQ411864) was conspicuously different from that of the isolate from Qingdao, China sequenced in the present work, indicating that they are different species. The isolate from Qingdao was verified as L. rostratum by morphological analysis, and the published morphology of existing GenBank record of L. rostratum is different from it. Based on both morphological and molecular evidence, the latter may be congeneric with an undescribed species of Loxophyllum from Guangdong Province, China. 相似文献