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Mitochondrial genomes of Tapes dorsatus and Cardita variegata:insights into Heteroconchia phylogeny
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作者 Xumin WANG Hua ZHANG +6 位作者 Xindong TENG Wenhui SUN Zhikai XING Shuang WANG Xiumei LIU Jiangyong QU Lijun WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期943-959,共17页
Heteroconchia,a widespread and abundant aquatic invertebrate,is an important clade of bivalve mollusks.The relationship between the three branches of Heteroconchia,Palaeoheterodonta,Archiheterodonta,and Euheterodonta ... Heteroconchia,a widespread and abundant aquatic invertebrate,is an important clade of bivalve mollusks.The relationship between the three branches of Heteroconchia,Palaeoheterodonta,Archiheterodonta,and Euheterodonta has become a main controversy in molecular studies of the relationships between bivalves.In the present study,we assembled the complete mitochondrial genomes of Tapes dorsatus(Veneridae)and Cardita variegata(Carditidae)using high-throughput sequencing.C.variegata is the first mitochondrial genome belonging to the family Carditidae to be reported.We used 12 protein coding genes(excluding atp8)from the complete mitochondrial genomes of 146 species to recover the internal relationships of Heteroconchia.Our results support the traditional view of early branching of Palaeoheterodonta and the recovery of the monophyly of Palaeoheterodonta,Anomalodesmata,Imparidentia.Rearrangement analysis show that gene arrangement within Venerida was highly variable.Time-calibrated phylogenetic studies based on a relaxed molecular clock model suggested that Veneridae originated approximately 337.62 million years ago(Ma)and split into two major clades,whereas Carditidae originated approximately 510.09 Ma.Our results provide evidence of the internal relationships of Heteroconchia. 展开更多
关键词 Tapes dorsatus Cardita variegata mitochondrial genome phylogeny
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Phylogeny,character evolution,and classification of Selaginellaceae(lycophytes) 被引量:2
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作者 Xin-Mao Zhou Li-Bing Zhang 《Plant Diversity》 SCIE CAS CSCD 2023年第6期630-684,共55页
Selaginella is the largest and most taxonomically complex genus in lycophytes.The fact that over 750 species are currently treated in a single genus makes Selaginellales/Selaginellaceae unique in pteridophytes.Here we... Selaginella is the largest and most taxonomically complex genus in lycophytes.The fact that over 750 species are currently treated in a single genus makes Selaginellales/Selaginellaceae unique in pteridophytes.Here we assembled a dataset of six existing and newly sampled plastid and nuclear loci with a total of 684 accessions(74%increase of the earlier largest sampling)representing ca.300 species to infer a new phylogeny.The evolution of 10 morphological characters is studied in the new phylogenetic context.Our major results include:(1)the nuclear and plastid phylogenies are congruent with each other and combined analysis well resolved and strongly supported the relationships of all but two major clades;(2)the Sinensis group is resolved as sister to S.subg.Pulviniella with strong support in two of the three analyses;(3)most morphological characters are highly homoplasious but some characters alone or combinations of characters well define the major clades in the family;and(4)an infrafamilial classification of Selaginellaceae is proposed and the currently defined Selaginella s.l.is split into seven subfamilies(corresponding to the current six subgenera t the Sinensis group)and 19 genera(the major diagnosable clades)with nine new species-poor genera.We support the conservation of Selaginella with a new type,S.flabellata,to minimize nomenclatural instability.We provide a key to subfamilies and genera,images illustrating their morphology,their morphological and geographical synopses,a list of constituent species,and necessary new combinations.This new classification will hopefully facilitate communication,promote further studies,and help conservation. 展开更多
关键词 Generic classification HOMOPLASY Lycophyte phylogeny Megaspore types MICROSPORES Nuclear 18S and 26S genes
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Improved mammalian family phylogeny using gap-rare multiple sequence alignment:A timetree of extant placentals and marsupials 被引量:1
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作者 Gao-Ming Liu Qi Pan +14 位作者 Juan Du Ping-Fen Zhu Wei-Qiang Liu Zi-Hao Li Ling Wang Chun-Yan Hu Yi-Chen Dai Xiao-Xiao Zhang Zhan Zhang Yang Yu Meng Li Peng-Cheng Wang Xiao Wang Ming Li Xu-Ming Zhou 《Zoological Research》 SCIE CSCD 2023年第6期1064-1079,共16页
The timing of mammalian diversification in relation to the Cretaceous-Paleogene(KPg)mass extinction continues to be a subject of substantial debate.Previous studies have either focused on limited taxonomic samples wit... The timing of mammalian diversification in relation to the Cretaceous-Paleogene(KPg)mass extinction continues to be a subject of substantial debate.Previous studies have either focused on limited taxonomic samples with available whole-genome data or relied on short sequence alignments coupled with extensive species samples.In the present study,we improved an existing dataset from the landmark study of Meredith et al.(2011)by filling in missing fragments and further generated another dataset containing 120 taxa and 98 exonic markers.Using these two datasets,we then constructed phylogenies for extant mammalian families,providing improved resolution of many conflicting relationships.Moreover,the timetrees generated,which were calibrated using appropriate molecular clock models and multiple fossil records,indicated that the interordinal diversification of placental mammals initiated before the Late Cretaceous period.Additionally,intraordinal diversification of both extant placental and marsupial lineages accelerated after the KPg boundary,supporting the hypothesis that the availability of numerous vacant ecological niches subsequent to the mass extinction event facilitated rapid diversification.Thus,our results support a scenario of placental radiation characterized by both basal cladogenesis and active interordinal divergences spanning from the Late Cretaceous into the Paleogene. 展开更多
关键词 MAMMALS phylogeny DIVERSIFICATION Evolutionary model
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Phylogeny and Geographical Derivation of Genus Hildenbrandia Based on Morphological and Molecular Evidence
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作者 NAN Fangru ZHAO Huiying +5 位作者 LI Juan LIU Xudong LIU Qi LV Junping FENG Jia XIE Shulian 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第6期1649-1659,共11页
The marine and freshwater Hildenbrandia samples were collected from diverse locations of China and Japan,and mor-phological characterization and molecular phylogenetic analysis were conducted on these samples.Morpholo... The marine and freshwater Hildenbrandia samples were collected from diverse locations of China and Japan,and mor-phological characterization and molecular phylogenetic analysis were conducted on these samples.Morphological measurements of freshwater specimens were consistent with the results of H.jigongshanensis,whereas cell dimensions of marine specimens were slightly larger than those of widely distributed H.rubra and H.crouanii.Phylogenetic trees based on rbcL,psbA and UPA sequences were consistent.Freshwater specimens collected in this study formed an independent clade with H.jigongshanensis supported by high values.Species attribution was confirmed further by the similar ITS2 secondary structures among the samples of H.jigongshan-ensis.It was found that the intraspecific divergence of rbcL gene in H.jigongshanensis was smaller than other two freshwater species H.rivularis and H.angolensis.Phylogenetic trees showed that marine specimens in this study grouped together with H.rubra samples of North America,and were different with the H.rubra samples of Europe.Combining the comparison results of CBC numbers in ITS2 secondary structure,we propose the marine samples collected in this study to be a new species Hildenbrandia qingdaoensis sp.nov.The separation of the marine and freshwater specimens was supported by the rbcL,UPA and psbA phylogeny as well as ITS2 se-condary structure inference.Biogeographical reconstruction showed the ancestor of freshwater Hildenbrandia might derive from South America and dispersed from North America to Europe and then to Asian countries,which needs to be verified further with more sam-ples and molecular evidences from South America. 展开更多
关键词 Hildenbrandia morphology molecular phylogeny ITS secondary structure BIOGEOGRAPHY
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Antibiogram, Genomic and Phylogeny of Stool and Seafood Isolates from Some Cholera-Prone Coastal Communities in Rivers State, Nigeria
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作者 Chidimma Anthonia Azike Vivian Nkemkanma Agi +3 位作者 Easter Godwin Nwokah Amba Ollor Ollor Clement Ugochukwu Nyenke Confidence Kinikanwo Wachukwu 《Journal of Biosciences and Medicines》 2023年第4期385-406,共22页
Cholera is a significant public health threat across the globe, especially in coastal regions with poor water supply. This study was carried out to determine the antibiogram, genomic, and phylogeny of stool and seafoo... Cholera is a significant public health threat across the globe, especially in coastal regions with poor water supply. This study was carried out to determine the antibiogram, genomic, and phylogeny of stool and seafood isolates from some cholera-prone coastal communities in Rivers State, Nigeria. A total of 400 stool samples and 42 different seafood were aseptically collected and examined using standard microbiology and molecular techniques. An antibiogram of isolates from seafood and stool samples was assayed. Genes for virulence, resistance, and relatedness of bacteria identified were also determined. The isolates from the stool and seafood were examined for susceptibility to some selected antibiotics. The findings showed the prevalence rate of cholera in the communities as follows: 16% in Kaa, 30% in Andoni, 4% in Ogu/Bolo, and 10% in Abua/Odual. The isolates from stool were susceptible to Ciprofloxacin and Gentamycin with a susceptibility rate of 94.12% each while 100% resistance was recorded against Amoxicillin-clavulanic acid, 94.12% against Amikacin and 88.24% against Colistin. For the sea foods, the isolates were susceptible to gentamycin and ciprofloxacin with a susceptibility rate of 91.43% and 82.86% respectively. Resistance was also recorded against Colistin (88.57%) and Azithromycin (82.86%). Testing the isolates for the presence of 16SrRNA genes showed that all were positive with 1500 bp 16SrRNA gene band size. TEM, OXA, SHV, and CTX-M resistant genes were detected whereas the virulence genes were TDH and AcrB. The phylogenetic analysis revealed isolates from seafood to be Aeromonas dhakensis, Vibrio parahaemolyticus, Vibrio azureus, and Providencia rettgeri, while in stool samples they were Enterobacter sichuanensis, Enterobacter hormaechei, Providencia sneebia, and Proteus vulgaris. Providencia stuartii, Proteus mirabilis, Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae were common isolates from both seafood and stool samples. This study has shown that not all reported cases of cholera are caused by Vibrio cholerae. Therefore, attention should be paid to other water-borne bacteria in every outbreak, especially in coastal communities. 展开更多
关键词 CHOLERA ANTIBIOGRAM Genomics phylogeny Virulence Coastal
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Phylogeny of Apaturinae Butterflies (Lepidoptera: Nymphalidae) Based on Mitochondrial Cytochrome OxidaseⅠ Gene 被引量:4
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作者 张敏 曹天文 +3 位作者 张睿 郭亚平 段毅豪 马恩波 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第9期812-823,共12页
The phylogenetic relationships of genera in the subfamily Apaturinae were examined using mtDNA sequence data from 1,471 bp of cytochrome oxidase subunit Ⅰ (COI). The mitochondrial COI gene from a total of 16 specie... The phylogenetic relationships of genera in the subfamily Apaturinae were examined using mtDNA sequence data from 1,471 bp of cytochrome oxidase subunit Ⅰ (COI). The mitochondrial COI gene from a total of 16 species in 11 genera were sequenced to obtain mtDNA data, along with those of 4 species obtained from GenBank, to construct the MP and the NJ trees using Athyma jina, Penthema adelma, Polyura nepenthes, and Charaxes bernardus as outgroups. The transitions at the third codon positions of the COI data set were found saturated, but they were retained for analysis, because they contain the majority of the phylogenetic information. The impacts of equal weight assumptions for all characters in the parsimonious analysis were assessed by potential alternations in clades in response to different transition/transversion weighting schemes. The results indicated four distinct major groups in Apaturinae. Moreover, several well supported and stable clades were found in the Apaturinae. The study also identified undetermined taxon groups whose positions were weakly supported and were subject to changes under different weighting schemes. Within the Apaturinae, the clustering results are approximately identical to the classical morphological classification. The mtDNA data suggest the genus Mimathyma as a monophyletic group. Lelecella limenitoides and Dilipa fenestra have close relationship with very strong support in all phylogenetic trees. It also supports the taxonomic revision of removing several species from Apatura to other genera, namely Mimathyma schrenckii, M. chevana, M. nycteis, Chitoria subcaerulea, C. fasciola, C. pallas, and Helcyra subalba. 展开更多
关键词 NYMPHALIDAE apaturinae MTDNA molecular phylogeny cytochrome oxidase gene
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Molecular Phylogeny of the Higher Category of Acrididae (Orthoptera: Acridoidea) 被引量:4
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作者 刘殿锋 董自梅 +4 位作者 张大羽 谷延泽 郭培军 韩瑞花 蒋国芳 《Zoological Research》 CAS CSCD 北大核心 2008年第6期585-591,共7页
The phylogenetic relationships among all taxa within the Acrididae (Orthoptera: Acridoidea) were largely unknown until now. In this study, to further investigations, 24 species of Acrididae from China were used as ... The phylogenetic relationships among all taxa within the Acrididae (Orthoptera: Acridoidea) were largely unknown until now. In this study, to further investigations, 24 species of Acrididae from China were used as sample taxa. The sequence constitutions and variations were analyzed and the molecular phylogenetic trees were reconstructed based on the combined sequence data (795bp length in total) of 12S rDNA and 16S rDNA, using the grasshopper Pyrgomorpha conica of Pyrgomorphidae as the outgroup. The results showed that the rates of the two kinds of transitions are obviously much higher than that of the four kinds of Wansversions in these combined 12S+16S rDNA sequence data. The saturation ofnucleotide substitutions happened in 12S and 16S rDNA sequence data. The molecular phylogenetic trees indicated that Oedipodinae is a monophyletic group and this subfamily is a natural one, but Catantopinae and Acridinae are non-monophyletic. Oedipodnae is a relatively primitive group within the Acrididae, whereas the Oxyinae may have diverged later than Oedipodinae, but earlier than most other species of Acridide. 展开更多
关键词 phylogeny ACRIDIDAE 16S rDNA 12S rDNA
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Phylogeny of Aceraceae Based on ITS and trn L-F Data Sets 被引量:12
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作者 田欣 郭振华 李德铢 《Acta Botanica Sinica》 CSCD 2002年第6期714-724,共11页
The nuclear encoded internal transcribed spacer (ITS) region and the plastid encoded trn L-F region were sequenced for 41 species of the Aceraceae, representing both genera Acer and Dipteronia, to reconstruct phylogen... The nuclear encoded internal transcribed spacer (ITS) region and the plastid encoded trn L-F region were sequenced for 41 species of the Aceraceae, representing both genera Acer and Dipteronia, to reconstruct phylogeny of this family, especially within Acer. The analyses were performed in separate and combined sequence data sets, with the Sapindaceae and Hippocastanaceae being selected as outgroups. It was indicated that the Aceraceae was monophyletic and D. sinensis was basal to the rest of the family but the two genera of it might be not monophyletic because Dipteronia dyerana was nested within Acer. The result inferred from the combined data showed greater resolution within Acer than that from the two separate data sets. The monophyly of most sections in Xu's system (1996) were supported with high bootstrap values, and some relationships between (or among) sections were also inferred, such as sect. Palmata and sect. Microcarpa; sect. Platanoidea, sect. Lithocarpa and sect. Macrophylla; sect. Integrifolia, sect. Trifoliata and sect. Pentaphylla; and sect. Acer, sect. Goniocarpa and sect. Saccharina (sensu Ogata). However, the sectional status and circumscriptions of some of the above-mentioned sections should be further adjusted. It seemed that the Xu's delimitations of sect. Rubra and sect. Saccharodendran should be revaluated. 展开更多
关键词 ACERACEAE phylogeny ITS sequences trnL-F sequences
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Molecular Phylogeny of the Lardizabalaceae Based on TrnL-F Sequences and Combined Chloroplast Data 被引量:5
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作者 王峰 李德铢 杨俊波 《Acta Botanica Sinica》 CSCD 2002年第8期971-977,共7页
The molecular phylogeny of the Lardizabalaceae is reconstructed based on chloroplast trn L_F sequences alone and combined trn L_F and rbc L sequences. The phylogenetic topologies agree well with Qin's and... The molecular phylogeny of the Lardizabalaceae is reconstructed based on chloroplast trn L_F sequences alone and combined trn L_F and rbc L sequences. The phylogenetic topologies agree well with Qin's and Takhtajan's tribal classification in both analyses. Decaisneae and Sinofranchetieae are basal clades in the phylogenetic trees and external to all other taxa in the family. Lardizabaleae consisting of Boquila and Lardizabala are well supported in both trn L_F (100%) analysis and trn L_F and rbc L combined analysis (99%). Tribe Akebieae are strongly supported by a bootstrap value of 100% in both trn L_F analysis and trn L_F and rbc L combined analysis. However, the new genus Archakebia is nested within the genus Akebia in the trn L_F trees. In the combined trees, Archakebia is sister to Akebia with high bootstrap support. The inter_relationships among three closely related genera Parvatia , Holboellia and Stauntonia are still problematic. P. brunoniana ssp. elliptica is sister to H. latifolia in both analyses with low bootstrap support. H. parviflora is nested within the Stauntonia and sister to S. cavalerieana . Therefore, these three genera of tribe Akebieae may not be monophylytic and their generic boundary and delimitation need to be further studied, by exploring more molecular data, together with more morphological characters. 展开更多
关键词 LARDIZABALACEAE molecular phylogeny trn L_F sequences rbc L sequences
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Molecular Phylogeny of Bisexual Artemia Based on 16S rDNA 被引量:5
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作者 印红 关妮 付育婷 《Agricultural Science & Technology》 CAS 2011年第5期659-662,共4页
[Objective] The research aimed at investigating the taxonomic position and phylogenetic relationship of bisexual brine shrimps.[Method] 16S rDNA of three species of bisexual Artemia from China was determined;the homol... [Objective] The research aimed at investigating the taxonomic position and phylogenetic relationship of bisexual brine shrimps.[Method] 16S rDNA of three species of bisexual Artemia from China was determined;the homologous sequences between them and 11 relative species of Artemia from GenBank were compared;the molecular phylogenetic tree was constructed by Mega Microsoft using Artemiopsis stefanssoni as outgroup.[Result] Artemia persimilis was the primal group in genus Artemia;Artemia franciscana and Artemia monica were the evolved groups;Artemia urmiana,Artemia sinica and other Artemia species from China shared a close genetic relationship.[Conclusion] Based on the 16S rDNA sequence of them,the phylogenetic relationships of these bisexual Artemia species were A.persimilis→A.urmiana,A.sinica and A.tibetiana→A.tunisiana→A.monica→A.Franciscan. 展开更多
关键词 Bisexual Artemia 16S rDNA Molecular phylogeny
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PHYLOGENY AND ZOOGEOGRAPHY OF THE CYPRINID GENUS Spinibarbus (Pisces: Cyprinidae) 被引量:3
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作者 杨君兴 陈银瑞 《Zoological Research》 CAS CSCD 1994年第S1期13-25,共13页
The cyprinid genus Spinibarbus consists of 5 species. They form into a monophyly by three synapomorphies. Based on 19 external and skeletal characters, the most parsimonious cladogram is constructed for Spinibarbus fi... The cyprinid genus Spinibarbus consists of 5 species. They form into a monophyly by three synapomorphies. Based on 19 external and skeletal characters, the most parsimonious cladogram is constructed for Spinibarbus fishes. Sister groups A (S. hollandi) and B-E (S. sinensis + S. denticulatus + S. yunnanensis + S. polylepis) represent the first phyletic branching within the genus Spinibarbus. The phyletic division of second sister groups B (S. sinensis) and C-E (S. denticulatus + S. yunnanensis + S. polylepis) is supposed to be resulted from the upheaval of Yunnan-Guizhou Plateau and the subsequent drainages' division. The phyletic division of third sister groups C (S. denticulatus) and D^E (S. yunnanensis + S. polylepis) is supposed to be resulted from the environmental differentiation between Yunnan-Guizhou Plateau and the lowlands of middle and lower Pearl and Yuanjiang Rivers. 展开更多
关键词 phylogeny ZOOGEOGRAPHY Spinibarbus
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Phylogeny of Saururaceae Inferred from matR Sequence Data 被引量:2
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作者 孟少武 陈之端 +1 位作者 李德铢 梁汉兴 《Acta Botanica Sinica》 CSCD 2001年第6期653-656,共4页
首次报道了三白草科 3个种及其外类群齐头绒 (ZippeliabegoniaefoliaBl.)的matR基因序列。研究材料包括三白草科现存的所有 6个种和两个选定外类群 ,分析软件是PAUP 4.0b 4a。分别采用最大简约法、距离法和最大似然法进行分析 ,都得到... 首次报道了三白草科 3个种及其外类群齐头绒 (ZippeliabegoniaefoliaBl.)的matR基因序列。研究材料包括三白草科现存的所有 6个种和两个选定外类群 ,分析软件是PAUP 4.0b 4a。分别采用最大简约法、距离法和最大似然法进行分析 ,都得到一个同样的系统发育树 ,只是支持率有所不同。结果显示三白草科是一个单系 ,Anemopsis是Houttuynia的姐妹群 ,并且 ,它们构成三白草科的第一个分支 ,是Gymnotheca_Saururus支的姐妹群。Gymnotheca和Saururus的姐妹群关系也被强烈支持。 展开更多
关键词 Saururaceae phylogeny matR gene sequences
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Phylogeny of the true water bugs(Hemiptera-Heteroptera:Nepomorpha) based on four Hox genes 被引量:1
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作者 李敏 王菁 +3 位作者 田晓轩 谢强 刘华希 卜文俊 《Entomotaxonomia》 CSCD 北大核心 2012年第1期35-44,共10页
The phylogenetic relationships among the Nepomorpha (Hemiptera: Heteroptera) were analyzed based on nuclear protein coding genes-partial sequences of four Hox genes: abd-A, Dfd, Ubx and pb. Fifteen taxa, of which ... The phylogenetic relationships among the Nepomorpha (Hemiptera: Heteroptera) were analyzed based on nuclear protein coding genes-partial sequences of four Hox genes: abd-A, Dfd, Ubx and pb. Fifteen taxa, of which eleven were ingroups representing ten of the eleven families, were selected to produce a phylogenetic inference of nepomorphan superfamilial or familial relationships via parsimony and Bayesian techniques. Our results supported the monophylies of Nepomorpha, Naucoroidea (Aphelocheiridae + Naucoridae), Nepoidea (Belostomatidae + Nepidae), Ochteroidea (Ochteridae + Gelastocoridae) and Pieoidea (Pleidae + Helotrephidae); the most basal lineage of Ochteroidea; Notonectoidea contained Notonectidae only and formed a new sister relationship with (Pleoidea + Naucoroidea); and the sister relationship of (Nepoidea + Corixoidea). The Hox genes are suitable molecular markers to resolve phylogenetic relationships at superfamily or family levels in Heteroptera. 展开更多
关键词 Nepomorpha phylogeny Hox genes
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Molecular Phylogeny and Phylogeography of Suidae 被引量:1
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作者 吴桂生 庞峻峰 张亚平 《Zoological Research》 CAS CSCD 北大核心 2006年第2期197-201,共5页
Although the Suidae animals were one of the most prosperous mammals, their taxa and phylogeny were poorly studied. To bridge this research gap, the complete mitochondrial DNA cyt b sequences (1140 bp)of one red rive... Although the Suidae animals were one of the most prosperous mammals, their taxa and phylogeny were poorly studied. To bridge this research gap, the complete mitochondrial DNA cyt b sequences (1140 bp)of one red river pig ( Potamochoerus porcus ), one bearded pig ( Sus barbatus ), and several Eurasian wild boars ( Sus scorfa ) were determined with direct PCR sequencing method. Incorporated with the sequences of other Suidae species obtained from GenBank, the phylogentic trees of Suidae species were constructed by Neighbor-Joining and Most Parsimony method. Our resuits showed that the babirousa was sister group of all other species. The African species clustered into a single clade, while the Eurasian species formed the other clade. The phylogenetic positions of the Sus species were consistent with their geographical distribution. Based on our phylogeographical results, the Sus species could be classified into three groups: (1) the relatively primitive animals from Philippine Islands (such as S. cebifrons and S. philippensis ), Sulawesi and it's adjacent islands (S. celebensis), (2) the Eurasian wild boars (S. scrofa and the mysterious S. salvanius), and (3) other pigs (such as S. barbatus and S. verrucosus), which might further diverged as the islands type (such as S. barbatus from Sumatra and Borneo) and the continental type (such as Malay Peninsula wild boar). 展开更多
关键词 SUIDAE phylogeny PHYLOGEOGRAPHY Mitochondrial DNA Cytochrome b PIGS
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16S rRNA Gene-Based Analysis of Ileal Bacterial Community and Phylogeny in Nursing and Weaned Piglets 被引量:1
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作者 王升平 柏美娟 +4 位作者 孔祥峰 吴信 黄瑞林 李铁军 印遇龙 《Animal Husbandry and Feed Science》 CAS 2009年第4期12-17,共6页
Weaning of piglets is generally considered as a stressor which changes intestinal ecosystem and leads to clinical implications. Microbiota inhabiting in small intestine (especially ileum) are assumed to promote heal... Weaning of piglets is generally considered as a stressor which changes intestinal ecosystem and leads to clinical implications. Microbiota inhabiting in small intestine (especially ileum) are assumed to promote health, but their functional properties are yet poody dascdbed. As indicated by the 16S rRNA gene sequences of ileal micrebiota in nursing piglets (at the age of 21 and 28 d) and 28-day-old weaned piglets (weaned at 21 d of age), the microbiota were mainly comprised of gram-positive bacteria. There were 40 operational taxonomic units (OTUs) (from 171 clones) in the ileum of nursing piglets aged 21 d, 61 OTUs (from 194 clones) in the ileum of nursing piglets aged 28 d, and 56 OTUs (from 171 clones) in the ileum of weaned piglets aged 28 d. The flea of nursing piglets aged 21 d were dominantly occupied by Lactobacilli (87.7%) as well as Streptococ cus ( 3.5 % ). Lactobacillus amy/ovorus (41.5 % ), Lactobaci/lus sp. ( 19.3 % ), Lactobaci/lus reuteri ( 12.3 % ), Lactobacillus salivarius ( 9.4 % ) and L. mucosae (4.7%) were the predominant species among Lactobacil/L Similar results were obtained in the nursing piglets at 28 d of age ex- cept that Lactobaci/li decreased to 71.1% and Streptococcus increased to 21.1% significantly. Lactobacillus (52.0%) and Streptococcus (26.3%) were the two major groups in the ileum of weaned piglets aged 28 d. Lactobacillus amylovorus (31.6%) and Lactobaci/lus reuteri ( 16.4% ) was the two most important species in Lactobacillus. Therefore, Lactobacilli were predominant in the ileum of nursing and weaned piglets, and they had the highest diversity, followed by Streptococcus. The diversity of ileal microbiota was not different remarkably between the nursing piglets and the weaned piglets, but the composition changed significantly. These findings are helpful to understand ileal bacterial ecophysiology and further develop nutritional regimes to prevent or counteract complications during the weaning transition. 展开更多
关键词 PIGLETS Intestinal microbiota phylogeny DIVERSITY 16S rRNA gene
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Phylogeny in Chloranthus Swartz (Chloranthaceae) Inferred from Sequence Analysis of nrDNA ITS Region 被引量:3
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作者 孔宏智 陈之端 《Acta Botanica Sinica》 CSCD 2000年第7期762-764,共3页
The internal transcribed spacer (ITS) regions of nuclear ribosomal DNA from ten species of Chloranthus Swartz and two outgroup species of Sarcandra Gardn. were sequenced. The regions ranged in length from 654 to 663 b... The internal transcribed spacer (ITS) regions of nuclear ribosomal DNA from ten species of Chloranthus Swartz and two outgroup species of Sarcandra Gardn. were sequenced. The regions ranged in length from 654 to 663 bp, with ITS1 (285-290 bp) slightly longer than ITS2 (205-211 bp). Of the 669 aligned positions, 109 sites (56 in ITS1, 52 in ITS2, and one in 5.8S region) were phylogenetically informative. Only one most parsimonious tree of 252 steps was obtained in PAUP analysis when gaps were treated as the fifth state. The traditional division of Chloranthus on the basis of habit seems to be quite unnatural. Evidence from the sequence of ITS region, just as that from cytology and anatomy, strongly suggested the separation of the genus into two groups according to the characteristics of androecial organs: one contains C. angustifolius, C. nervosus, C. japonicus and C. fortunei, and the other comprises the remaining species. 展开更多
关键词 Chloranthus Swartz phylogeny ITS
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CRANIODENTAL VARIATION OF MACAQUES ( Macaca ): SIZE,FUNCTION AND PHYLOGENY
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作者 潘汝亮 Charles Oxnard 《Zoological Research》 CAS CSCD 2000年第4期308-322,共15页
In order to analyze skull variation in the genus Macaca ,seventy seven craniodental variables were taken from eleven species.They were first defined seven functional units comprising three anatomical regions.Twenty s... In order to analyze skull variation in the genus Macaca ,seventy seven craniodental variables were taken from eleven species.They were first defined seven functional units comprising three anatomical regions.Twenty seven variables were finally selected to carry out the morphology of the whole skull.The data,organized in these ways,were examined to discover variations between and within the various species.The methods used were Principal Components Analysis (PCA) and Discriminant Function Analysis (DFA).PCAs of the functional units anatomical regions,and the whole skull provided similar,though not identical,separations of species clusters in both sexes separately.These differences in structure could be related to size,sexual dimorphism,diet,ecology,classification and phylogeny.The question of size should have been easy to settle.Unfortunately,this is not the case.In this study where the raw data are measurements of the specimens,the main differences should be size.However,the size differences seem to occur in both the first and second (independent) multivariate axes.In some analyses the size differences between the species are biggest and appear in the first axis.In other analyses it is the separation between the sexes (and these too are largely size) that are the biggest and appear in the first axis.Yet in other analyses,both of these size separations,though still orthogonal to one another,present in the combination of the first two axes.This certainly implies that a single axis of body size is not present and that shape differences have not been isolated form size differences.It also implies that sexual dimorphism is a complex matter.As a result,the question of the relationships between the species is therefore also complex.One cluster of species that includes M fascicularis,M sinica and M radiata was significantly isolated from all others regardless of level of analysis.This relationship is quite different from that proposed on the anatomy of the reproductive organs (Delson,1980;Fooden,1976,1980). 展开更多
关键词 PRIMATES MACACA Craniodental variation Morphometric analysis Functional adaptation phylogeny
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A Molecular Phylogeny of Macaca Based on Mitochondrial Control Region Sequences 被引量:7
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作者 李青青 张亚平 《Zoological Research》 CAS CSCD 北大核心 2004年第5期385-390,共6页
Nucleotide sequences of segments of the mitochondrial control regions were analyzed to infer the phylogenetic relationships among 7 macaques.High nucleotide diversity in Macaca assamensis and relatively low diversity ... Nucleotide sequences of segments of the mitochondrial control regions were analyzed to infer the phylogenetic relationships among 7 macaques.High nucleotide diversity in Macaca assamensis and relatively low diversity in M.thibetana were found.Based on the ML tree from control regions,species in our study can roughly be sorted into three species groups except for the phylogenetic position of M.fascicularis,i.e.,silenus group,including M.leonina;sinica group,including M.arctoides,M.assamensis,and M.thibetana;and fascicularis group,including M.mulatta and M.cyclopis.A discrepancy between earlier studies (Fooden & Lanyon,1989;Tosi et al,2003a;Deinard & Smith,2001;Evans et al,1999;Hayasaka et al,1996;Morales & Melnick,1998),our result supported the hypothesis that M.fascicularis diverged earlier than M.leonina.Mitochondrial paraphyly in eastern M.mulatta (with respect to M.cyclopis) and eastern M.assamensis (with respect to M.thibetana) were clearly observed in our study.In accordance with the results of Y chromosome,allozyme,nuclear genes and some morphological data (Delson,1980;Fooden & Lanyon,1989;Fooden,1990;Tosi et al,2000,2003a,b;Deinard & Smith,2001),our study on control region sequences supported M.arctoides to be classified into the sinica group.However,this result disagreed with the previous mtDNA studies (Hayasaka et al,1996;Morales & Melnick,1998;Tosi et al,2003a). 展开更多
关键词 MACACA MACAQUE Mitochondrial DNA Control region phylogeny
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Complete genome sequence of the rifamycin SV-producing Amycolatopsis mediterranei U32 revealed its genetic characteristics in phylogeny and metabolism 被引量:11
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作者 Wei Zhao Yi Zhong +23 位作者 Hua Yuan Jin Wang Huajun Zheng Ying Wang Xufeng Cen Feng Xu Jie Bai Xiaobiao Han Gang Lu Yongqiang Zhu Zhihui Shao Han Yan Chen Li Nanqiu Peng Zilong Zhang Yunyi Zhang Wei Lin Yun Fan Zhongjun Qin Yongfei Hu Baoli Zhu Shengyue Wang Xiaoming Ding Guo-Ping Zbao 《Cell Research》 SCIE CAS CSCD 2010年第10期1096-1108,共13页
Amycolatopsis mediterranei is used for industry-scale production of rifamycin, which plays a vital role in antimyco- bacterial therapy. As the first sequenced genome of the genus Amycolatopsis, the chromosome of strai... Amycolatopsis mediterranei is used for industry-scale production of rifamycin, which plays a vital role in antimyco- bacterial therapy. As the first sequenced genome of the genus Amycolatopsis, the chromosome of strain U32 comprising 10 236 715 base pairs, is one of the largest prokaryotic genomes ever sequenced so far. Unlike the linear topology found in streptomycetes, this chromosome is circular, particularly similar to that of Saccharopolyspora erythraea and Nocardia farcinica, representing their close relationship in phylogeny and taxonomy. Although the predicted 9 228 protein-coding genes in the A. mediterranei genome shared the greatest number of orthologs with those of S. erythraea, it was unexpectedly followed by Streptomyces coelicolor rather than N. farcinica, indicating the distinct metabolic characteristics evolved via adaptation to diverse ecological niches. Besides a core region analogous to that common in streptomycetes, a novel 'quasicore' with typical core characteristics is defined within the non-core region, where 21 out of the total 26 gene clusters for secondary metabolite production are located. The rifamycin biosynthesis gene cluster located in the core encodes a cytochrome P450 enzyme essential for the conversion of rifamycin SV to B, revealed by comparing to the highly homologous cluster of the rifamycin B-producing strain S699 and further confirmed by genetic complementation. The genomic information of A. mediterranei demonstrates a metabolic network orchestrated not only for extensive utilization of various carbon sources and inorganic nitrogen compounds but also for effective funneling of metabolic intermediates into the secondary antibiotic synthesis process under the control of a seemingly complex regulatory mechanism. 展开更多
关键词 GENOME Amycolatopsis mediterranei RIFAMYCIN phylogeny P450 METABOLISM
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Phylogeny of the cuttlefishes (Mollusca: Cephalopoda) based on mitochondrial COI and 16S rRNA gene sequence data 被引量:11
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作者 LINXiangzhi ZHENGXiaodong +1 位作者 XIAOShu WANGRucai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第4期699-707,共9页
To clarify cuttlefish phylogeny, mitochondrial cytochrome c oxidase subunit I (COI) gene and partial 16S rRNA geneare sequenced for 13 cephalopod species. Phylogenetic trees are constructed, with the neighbor-joining ... To clarify cuttlefish phylogeny, mitochondrial cytochrome c oxidase subunit I (COI) gene and partial 16S rRNA geneare sequenced for 13 cephalopod species. Phylogenetic trees are constructed, with the neighbor-joining method.Coleoids are divided into two main lineages, Decabrachia and Octobrachia. The monophyly of the order Sepioidea,which includes the families Sepiidae, Sepiolidae and Idiosepiidae , is not supported. From the two families ofSepioidea examined, the Sepiolidae are polyphyletic and are excluded from the order. On the basis of 16S rRNA andamino acid of COI gene sequences data, the two genera (Sepiella and Sepia) from the Sepiidae can be distinguished, butdo not have a visible boundary using COI gene sequences. The reason is explained. This suggests that the 16S rDNAof cephalopods is a precious tool to analyze taxonomic relationships at the genus level, and COI gene is fitter at ahigher taxonomic level (i.e., family). 展开更多
关键词 phylogeny CEPHALOPODS CUTTLEFISH COI 16S rRNA
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