959 resultados para Phylogenetic


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测定人猿超科(人、黑猩猩、大猩猩、红毛猩猩和长臂猿)和旧大陆猴(猕猴和叶猴)7种高等灵长类FKN全基因序列,探讨其系统进化分析.用简并引物PCR(Degenerated PCR)法分别扩增FKN的3个外显子,其产物经琼脂糖凝胶回收、纯化后测序,然后用BioEdit软件剪切拼接FKN基因全序列,用DNAStar比对后比较基因和氨基酸序列同源性,Mega软件重构FKN基因进化树,应用Datamonkey分析FKN的负选择位点.序列分析发现人猿超科较旧大陆猴FKN基因除了有散在的点突变外,还有一明显的30 bp的核苷酸缺失突变;人FKN基因序列与黑猩猩、大猩猩、红毛猩猩、长臂猿、猕猴和叶猴的同源性分别是99.2%、98.4%、98.1%、96.5%%、95.95和93.8%,由此推导的氨基酸序列同源性分别是98.5%、98.0%、97.7%、94.7%、93.7%和90.5%;FKN基因进化树表明人与黑猩猩关系更近,FKN基因进化和通常认为的物种进化一致;Datamonkey分析结果显示FKN存在3个负选择位点53Q.84D、239N.成功获得人、黑猩猩、大猩猩、红毛猩猩、长臂猿、猕猴和叶猴7种高等灵长类物种FKN全基因序列,为后续探讨FKN在高等灵长类物种进化过程中免疫学功能演变及其结构与功能的关系奠定基础. 作 者: 洪晓武 张亚平 储以微 高海峰 蒋正刚 熊思东 HONG Xiao-Wu ZHANG Ya-Ping CHU Yi-Wei GAO Hai-Feng JIANG Zheng-Gang XIONG Si-Dong 作者单位: 洪晓武,储以微,高海峰,蒋正刚,熊思东,HONG Xiao-Wu,CHU Yi-Wei,GAO Hai-Feng,JIANG Zheng-Gang,XIONG Si-Dong(复旦大学上海医学院免疫学系,免疫生物学研究所,上海,200032) 张亚平,ZHANG Ya-Ping(中国科学院昆明动物研究所细胞与分子进化开放实验室,昆明,650223) 刊 名: 遗传 ISTIC PKU 英文刊名: HEREDITAS 年,卷(期): 2008 30(5) 分类号: Q94 关键词: 人猿超科 旧大陆猴 FKN 测序 进化分析 机标分类号: R5 S86 机标关键词: 大陆灵长类全基因序列测定系统进化分析phylogenetic analysis基因进化树黑猩猩序列同源性长臂猿物种进化猕猴红毛负选择氨基酸琼脂糖凝胶基因全序列序列分析位点软件重构 基金项目: 国家自然科学基金,复旦大学校科研和教改项目 DOI:

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下载PDF阅读器系统发育研究(phylogeny)不仅有助于重建地球所有生物体的进化历史,而且还可以揭示进化生物学领域中的一些基本问题.清晰了解各生物物种进化历程及不同物种之间的进化关系,是进一步研究和探索生物学其他学科的基础.但是现今广泛应用的所有系统发育分析方法都存在一定的局限性,在一定程度上不能有效消除各种误差,从而不能客观地处理和分析数据,也就不能成功重建生物进化历程,真实反映物种进化关系.系统发育研究中,"长枝吸引"(Long-branch Attraction,LBA)假象是最为困扰研究者的问题.文章从"长枝吸引"问题的产生原由、检测方法以及消除策略等多个方面进行详尽概述,并通过列举典型实例,阐述了解决"长枝吸引"问题的途径.

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Carnivora; Caniformia; Feliformia; Phylogenetic tree; Mitochondrial DNA; Nuclear genes; 【摘要】 追溯生物界不同生物类型的起源及进化关系,即重建生物类群的系统发育树是进化生物学领域中一个十分重要的内容。食肉目哺乳动物位于食物链顶端,很多成员不仅在我国野生动物保护工作中占有重要地位,而且还是研究动物适应性进化遗传机制的重要模式生物。因而,食肉目物种作为物种资源中的一个重要类群,其系统发育学一直是国内外研究的热门课题。构建可靠的食肉目分子系统树,无疑将具有重要的进化理论意义和保护生物学价值。鉴于目前食肉目各科间系统发育关系仍然处于“广泛争论”的状态,本文将针对食肉目科水平上的系统发育学研究进展,包括来自于形态学特征、细胞学及分子生物学方面的证据,做简要概述,并提出目前研究中存在的问题。这对今后食肉目系统发育方面的进一步研究工作具有指导意义,并为以该类群作为模式生物开展适应性进化研究奠定基础

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Mitochondrial DNA, purified from 36 samples of 23 local populations which are widely distributed in Vietnam, Burma, and 10 provinces of China, has been analyzed to model the phylogeny of rhesus monkeys. The 20 local populations of China may represent nearly all major populations in China. Using 20 restriction endonucleases of 6-bp recognition, we observed a total of 50-61 sites in the various samples. By combining the cleavage patterns for each enzyme, the 36 samples were classified into 23 restriction types, each of which was found exclusively in the respective population from which samples were obtained By combining the earlier study of Indian rhesus monkeys, phylogenetic trees, which have been constructed on the basis of genetic distance, indicate that rhesus monkeys in China, Vietnam, India, and Burma can be divided into seven groups. Integrating morphological and geographical data, we suggest that rhesus monkeys in China, Vietnam, and Burma may be classified into six subspecies-M. m. mulatta, M. m. brevicaudus, M. m. lasiotis, M. m. littoralis, M. m. vestita, and M. m. tcheliensis-and rhesus monkeys in India may be another valid subspecies. M. m. tcheliensis is the most endangered subspecies in China. Divergence among subspecies may have begun 0.9-1.6 Ma. The radiation of rhesus monkeys in China may have spread from the southwest toward the east. The taxonomic status of the Hainan monkey and the Taiwan monkey require further investigation.

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Mitochondrial DNA polymorphisms in 15 specimens of three species of slow lorises-Nycticebus coucang, N. intermedius, and N. pygmaeus-were analyzed in order to study the evolutionary relationships among the species. Eight restriction types were observed in the samples. Phylogenetic trees constructed on the basis of genetic distances showed that the slow lorises sort into two clusters: four types of N. coucang and three types of N. intermedius plus one type of N. pygmaeus. Our results suggest that there are two valid species in the genus Nycticebus-N. coucang and N. pygmaeus-and that N. intermedius should be included within N. pygmaeus. Divergence between the two species may have begun 2.7 Ma (million years ago). Evolution of gross morphology, chromosomes, and mitochondrial DNA in the slow lorises appears to be concordant.

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The phylogeny of Chinese leaf monkeys, especially the snub-nosed monkeys (Rhinopithecus), has not been thoroughly investigated using molecular sequence data, perhaps due to their rarity in the wild and their poor representation in institutional collections. Despite several proposed classifications, systematic relationships of these species remain poorly defined and this has hindered their conservation. To clarify the phylogenetic relationships of the leaf monkey clade in China, we sequenced the mitochondrial ND3, ND4L, ND4, tRNA(Arg), tRNA(His), tRNA(Ser), and tRNA(Leu) genes for Rhinopithecus bieti, R. roxellana, Trachypithecus francoisi, T. f. leucocephalus, and T. phayrei as well as Pygathrix nemaeus and Colobus guereza. We included a rotal of 2252 characters for each individual, excluding gaps in primary sequences. Our interpretation of the results from character- and distance-based phylogenetic analyses suggest that (1) Pygathrix nemaeus is sister to Rhinopithecus rather than to Trachypithecus though it is quite divergent from the former; (2) the Yunnan snub-nosed monkey, Rhinopithecus bieti, represents a valid species; (3) the white-headed leaf monkey is not a distinct species, but instead is a subspecies of Trachypithecus francoisi (T. f. leucocephalus), though it should still be considered a separate evolutionarily significant unit (ESU); and (4) because two individuals of the Phayrei's leaf monkey, T. phayrei, are genetically distinct from one another, a more extensive revision of the taxonomy of this putative species in China is needed. These results, plus ongoing work on the molecular systematics of the entire Asian leaf monkey radiation, can provide a sound basis for identifying the appropriate units of conservation for this endangered group of primates.

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The classification and phylogenetic relationships of the Old World monkeys are still controversial. For Asian colobines, from three to nine genera were recognized by different primatologists. In the present study, we have sequenced a 424 bp mitochondrial tRNA(Thr) gene and cytochrome b gene fragment from Macaca mulatta, Mandrillus sphinx, Mandrillus leucophaeus, Semnopithecus entellus, Trachypithecus vetulus, T. johnii, T. phayrei, T. francoisi, Pygathrix nemaeus, Rhinopithecus roxellanae, R. bieti, R. avunculus, Nasalis larvatus, and Colobus polykomos in order to gain independent information on the classification and phylogenetic relationships of those species. Phylogenetic trees were constructed with parsimony analysis by weighting transversions 5 or 10 fold greater than transitions. Our results support the following conclusions: (1) the Old World monkeys are divided into two subfamilies; (2) that among the colobines, Colobus, the African group, diverged first, and Nasalis and Rhinopithecus form a sister clade to Pygathrix; (3) that there are two clades within leaf monkeys, i.e. 1) S. entellus, T. johnii, and T. vetulus, and 2) T, phayrei and T. francoisi; (4) that Rhinopithecus avunculus, R. roxellanae, and R. bieti are closely related to each other, and they should be placed into the same subgenus; (5) that Rhinopithecus is a distinct genus; and (6) that the ancestors of Asian colobines migrated from Africa to Asia during the late Pliocene or early Pleistocene.

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The sequences of the mitochondrial ND4 gene (1339 bp) and the ND4L gene (290 bp) were determined for all the 14 extant taxa of the Drosophila nasuta subgroup The average A + T content of ND4 genes is 76.5% and that of ND4L genes is 83.5%. A total of 114 variable sites were scored. The ND4 gene sequence divergence ranged from 0 to 5.4% within the subgroup. The substitution rate of the ND4 gene is about 1.25% per million years. The base substitution of the genesis strongly transition biased. Neighbor-joining and parsimony were used to construct a phylogeny based on the resultant sequence data set. According to these trees, five, distinct mtDNA clades can be identified. D. niveifrons represents the most diverged lineage. D, sulfurigaster bilimbata and D. kepulauana form two independent lineages. The other two clades are the kohkoa complex and the albomicans complex. The Kohkoa complex consists of D. sulfurigaster sulfurigaster, D. pulaua, D. kohkoa, and Taxon-F. The albomicans complex can be divided into two groups: D. nasuta, D. sulfurigaster neonasuta, D. sulfurigaster albostrigata, and D.. albomicans from Chiangmai form one group; and D. pallidifrons, Taxon-I, Taxon-J, and D. albomicans from China form the other group. High genetic differentiation was found among D. albomicans populations. Based on our phylogenetic results, we hypothesize that D. niveifrons diverged first from the D, nasuta subgroup in Papua New Guinea about 3.5 Mya. The ancestral population spread to the north and when it reached Borneo, it diversified sequentially into the kohkoa complex, D. s. bilimbata, and D. kepulauana. About 1 Mya, another radiation occurred when the ancestral populations reached the Indo-China Peninsula, forming the albomicans complex. Discrepancy between morphological groupings and phylogenetic results suggests that the male morphological traits may not be orthologous. (C) 1999 Academic Press.

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Mitochondrial cytochrome b genes of about 450 bp fragments from 3 proturan species, 5 collembolan species and 2 dipluran species have been sequenced. The number of nucleotide substitutions and Kimura 2-parameter distances have also been calculated, and a series of molecular phylogenetic trees reconstructed by using parsimony and distance methods. The proturan, collembolan and dipluran species have evolved monophyletic groups. The results suggest that Protura and Collembola are sister groups, while Diplura is more or less demonstrating a closer phylogenetic relationship to the pterygotan insects. The phylogeny and their systematic position of protura and other groups are also discussed.

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In this study, the region corresponding to the Thr-Gly region of the period (per) gene in the Drosophila nasuta subgroup of species was sequenced. The results showed, that this region was highly conserved in the D. nasuta subgroup. There were only nine variable sites found in this 300-bp-long region, all located in two small regions highly variable among Drosophila species. No length variation was observed either within this subgroup or in the Yunnan (YN) population of D. albomicans. The deduced amino acid sequences were identical for all 14 taxa in the D. nasuta subgroup, and a stretch of alternating Thr-Gly pairs was not observed in this subgroup. A phylogenetic tree was constructed. The clustering of some species was in general agreement with previous works, but it also raised some question on the phylogenetic relationship between the nasuta species. The data did not implicate the Thr-Gly region playing a role in behavioral isolation in this subgroup of Drosophila.

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Random amplified polymorphic DNA (RAPD) markers are used to investigate genetic variation and evolutionary relationships of 29 samples of Cordyceps sinensis from different geographical populations on the Qinghai-Tibet plateau. Out of 137 RAPD bands scored, 100 are polymorphic. A correlation is revealed between geographical distance and genetic distance. The molecular phylogenetic tree suggests that the 29 samples are divided into three notable clusters, corresponding to the geographical populations, i.e., the north population (NP), middle population (MP), and south population (SP). The NP consists of 7 northern samples from Menyuan, Maqu, and Luqu, the MP consists of 8 samples from Yushu and Chengduo, and the SP consists of 14 samples from Byma Snow Mountain, Renzhi Snow Moutain, Chongcaoxiwa, and Dacaodi. It is demonstrated that extensive genetic diversity is found among different geographical populations of C. sinensis. The genetic diversity pattern of C. sinensis may be caused by the founder effects. The taxonomic status of NP, MP, and SP populations should be that they are different subspecies rather than different species.

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The chemokine receptor CCR5 can serve as a coreceptor for M-tropic HIV-1 infection and both M-tropic and T-tropic SIV infection. We sequenced the entire CCR5 gene from 10 nonhuman primates: Pongo pygmaeus, Hylobates leucogenys, Trachypithecus francoisi, Trachypithecus phayrei, Pygathrix nemaeus, Rhinopithecus roxellanae, Rhinopithecus bieti, Rhinopithecus avunculus, Macaca assamensis, and Macaca arctoides. When compared with CCR5 sequences from humans and other primates, our results demonstrate that:(1) nucleotide and amino acid sequences of CCR5 among primates are highly homologous, with variations slightly concentrated on the amino and carboxyl termini; and (2) site Asp13, which is critical for CD4-independent binding of SIV gp120 to Macaca mulatta CCR5, was also present in all other nonhuman primates tested here, suggesting that those nonhuman primate CCR5s might also bind SIV gp120 without the presence of CD4. The topologies of CCR5 gene trees constructed here conflict with the putative opinion that the snub-nosed langurs compose a monophyletic group, suggesting that the CCR5 gene may not be a good genetic marker for low-level phylogenetic analysis. The evolutionary rate of CCR5 was calculated, and our results suggest a slowdown in primates after they diverged from rodents. The synonymous mutation rate of CCR5 in primates is constant, about 1.1 x 10(-9) synonymous mutations per site per year. Comparisons of K-a and K-s suggest that the CCR5 genes have undergone negative or purifying selection. K-a/K-s ratios from cercopithecines and colobines are significantly different, implying that selective pressures have played different roles in the two lineages.

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Ten restriction endonucleases were used to investigate the mitochondrial DNA restriction fragment length polymorphism (mtDNA RFLP) of 11 native cattle breeds and one cultivated cattle breed in South China. Twenty-three restriction morphs were detected, which can be sorted into five haplotypes, A phylogenetic tree of the haplotypes was constructed by using the 'upgma' method. Our study showed that haplotype I and II are identical to the zebu (Bos indicus) and taurine (Bos taurus) haplotypes, respectively. Zebu and taurine were the two major origins of cattle populations in South China, and the zebu probably had more influence on the native cattle population than taurine did. Haplotype III is identical to haplotype I of yak (Bos grunniens), which was only detected in the Diqing cattle breed. Haplotype IV was detected for the first time. This haplotype, found only in Dehong cattle, might be from an independent domestication event, probably from another Bos indicus population. Divergence of haplotypes I and IV occurred about 268,000-535 000 years ago, much earlier than the 10,000-year history of cattle husbandry. Our results also suggest a secondary introgression of mtDNA from yak to Diqing cattle.

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The mitochondrial cytochrome oxidase II (Co II) from four different apterygotens Cryptopygus nanjiensis (Collembola), Neanura latior (Collembola), Gracilentulus maijiawensis (Protura) and Lepidocampa weberi (Diplura) were sequenced. Their A+T content, number of nucleotide substitutions, TV/TV ratio; and Tamura-Nei's distance were calculated. A series of phylogenetic trees were constructed by parsimony and distance methods using a crustacean Artemia franciscana as outgroup, Finally the evolutionary trend A+T content of CO II genetic divergence and phylogenetic relationship of apterygotan groups were discussed.

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In total, 1218 Chinese from twelve ethnic groups and nine Han geographic groups were screened for the mtDNA 9-bp deletion motif. The frequency of the 9-bp deletion in all samples was 14.7% but ranged from 0% to 32% in the various ethnic groups. Three individuals had a triplication of the 9-bp segment. Phylogenetic and demographic analyses of the mtDNA hypervariable segment 1 (HVS1) sequences suggest that the 9-bp deletion occurred more than once in China. The majority of the Chinese deletion:haplotypes (about 90%) have a common origin as a mutational event following an initial expansion of modem humans in eastern Asia. Other deletion haplotypes and the three haplotypes with a 9-bp triplication may have arisen independently in the Chinese, presumably by replication error. HVS1 haplotype analysis suggests two possible migration routes of the 9-bp deletion in east and southeast Asia. Both migrations originated in China with one route leading to the Pacific Islands via Taiwan, the other to southeast Asia and possibly the Nicobar Islands. Along both routes of peopling, a decrease in HVS1 diversity of the mtDNA haplotypes is observed. The "Polynesian motif (16217T/C, 16247A/G, and 16261C/T)" and the 16140T/C, 16266C/A, or C/G polymorphisms appear specific to each migration route.