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1.
分子系统学研究进展   总被引:14,自引:0,他引:14  
分子系统学 ( molecular systematics)是近 30年发展起来的一门综合性前沿学科 ,它在分子水平上对生物进行遗传多样性、分类、系统发育和进化等方面的研究 ,其研究结果对于保护生物多样性 (尤其是遗传多样性 ) ,揭示生物进化历程及机理具有十分重要的意义。1 分子系统学的定义及发展简史分子系统学是通过检测生物大分子包含的遗传信息 ,定量描述、分析这些信息在分类、系统发育和进化上的意义 ,从而在分子水平上解释生物的多样性、系统发育及进化规律的一门学科。它以分子生物学、系统学、遗传学、分类学和进化论为理论基础 ,以分子生物学…  相似文献   

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从基因组DNA的提取、研究的基因片段、PCR引物选用、扩增条件以及叶蝉科不同阶元的分子系统发育分析等方面,综述叶蝉科(半翅目:叶蝉科)昆虫分子系统发育的研究进展。目前角顶叶蝉类的研究成果相对较多,大叶蝉亚科次之,其余类群的研究较少或无。线粒体基因与核基因序列联合分析以及线粒体全序列分析以及基因序列与形态数据相结合分析,分子鉴定叶蝉与共生菌之间的协同进化的研究,将是叶蝉分子系统学未来发展的主要研究手段。  相似文献   

4.
螟蛾是常见的中、小型蛾类,其分子系统学研究在近十年发展迅速。本文总结了利用分子系统学方法在螟蛾进化与系统发育关系重建、物种鉴定、近缘种的鉴别和隐存种的发现以及谱系动物地理学、种群遗传变异和分化等方面的研究进展。  相似文献   

5.
Trochoidea are a large superfamily of morphologically and ecologically diverse marine gastropods. We present here an appraisal of the composition and relationships among trochoidean families based on molecular data, with an especial focus on the family Trochidae. Bayesian analyses of sequences from three genes (18S rRNA, 28S rRNA and COI) including data from 162 vetigastropod species show that the gastropod family Trochidae (sensu  Hickman & McLean (1990 ), Natural History Museum Los Angeles County Science Series, 35, 1–169) is not monophyletic. Recognition of Chilodontidae, Solariellidae and Calliostomatidae at the family level is supported. Our new, more limited, definition of Trochidae includes the subfamilies Stomatellinae, Lirulariinae and Umboniinae and redefined Trochinae, Cantharidinae and Monodontinae. Halistylinae are provisionally retained in the Trochidae based on previous morphological studies. As redefined, Trochidae are a predominantly shallow‐water radiation in the tropics and subtropics. Some subfamilies and genera previously included in Trochidae have been moved to an enlarged family Turbinidae. The family Turbinidae has been redefined to include Turbininae, Skeneinae, Margaritinae, Tegulinae, Prisogasterinae and most surprisingly the commercially important genus Tectus Montfort, 1810. The new definition of Turbinidae means that the family includes both predominantly shallow and deep‐water clades as well as genera that are distributed across the globe from the poles to the tropics. A greater range of habitat is now seen in Turbinidae than in Trochidae. The redefined Trochidae and Turbinidae, together with Solariellidae, Calliostomatidae and Liotiidae, make up the superfamily Trochoidea. Phasianellidae and Colloniidae are recognized as belonging in a new superfamily, Phasianelloidea, and Angaria Röding, 1798 is recognized as belonging in a new superfamily, Angarioidea. Placement of Areneidae into a superfamily awaits further work.  相似文献   

6.
This study is the most extensive molecular study of the gastropod families Trochidae and Calliostomatidae published to date, in terms of both numbers of taxa and of gene sequences. As a result of Bayesian phylogenetic analyses of molecular sequence data from one nuclear gene and three mitochondrial genes, we propose dramatic changes to Trochidae family systematics, present the first molecular phylogeny for Calliostomatidae and include the first published sequence data for the enigmatic subfamily Thysanodontinae. Our phylogeny demonstrates that within the family Trochidae there is strong support for three subfamilies new to traditional classifications: Alcyninae subfam. nov., Fossarininae and Chrysostomatinae subfam. nov. As proposed, Alcyninae consists only of the nominotypical genus Alcyna, which is sister to all other trochids. The subfamily Fossarininae, as defined here, includes Fossarina, Broderipia, Synaptocochlea and “Royaeximia and probably also Clydonochilus and Minopa. The subfamily Chrysostomatinae comprises the genera Chrysostoma and Chlorodiloma. Additional molecular support is also obtained for recently redefined Trochinae, Monodontinae, and Cantharidinae and for the traditionally recognised subfamilies Umboniinae and Stomatellinae. The subfamily Lirulariinae is not supported by the molecular data, but rather is incorporated into Umboniinae. We also demonstrate that the current concept of the subfamily Margaritinae (previously a trochid subfamily, but recently and provisionally assigned to Turbinidae) is not monophyletic. We provide preliminary evidence that whereas Margarella rosea (previously a member of Margaritinae) belongs in the trochid subfamily Cantharidinae, its presumptive congener M. antarctica is not a trochid, but instead clusters with the thysanodontine genus Carinastele. Based on the phylogenetic placement of C. kristelleae, we agree with previous proposals based on morphological data that Thysanodontinae are more closely related to Calliostomatidae than Trochidae. Both Calliostoma and Carinastele are carnivorous and if a sister relationship can be confirmed between Carinastele and Margarella antarctica it might mean that carnivory evolved twice in Trochoidea. The direction of dietary changes was not investigated in this study, but mapping diet onto the phylogeny suggests that true herbivory is predominantly a derived character. The new classification system also means that five trochid subfamilies are predominantly associated with hard substrata, one with soft substrata (Umboniinae) and two with algae and seagrass (Alcyninae and Cantharidinae). There has been a shift back to hard substrata in one umboniine clade. Two of three clades within Calliostomatidae were predominantly associated with hard substrata, but one Japanese clade is associated with sand. The finding of three new, unidentified species from very deep water means that Trochidae, like Calliostomatidae, now includes species found at bathyal depths. More deep-water species may be found as increased sampling leads to the discovery of new species.  相似文献   

7.
蜱类系统学研究进展   总被引:5,自引:0,他引:5  
杨晓军  陈泽  刘敬泽 《昆虫学报》2007,50(9):941-949
本文介绍了近年来蜱的编目和分类及系统发育和演化等方面的研究进展。对软蜱科(Argasidae)说明了属的变动;硬蜱科(Ixodidae)介绍了璃眼蜱亚科(Hyalomminae)和凹沟蜱亚科(Bothriocrotoninae)以及相应变动的属(新建的凹沟蜱属Bothriocroton和须角蜱属Cornupalpatum,合并的牛蜱属Boophilus、暗眼蜱属Anocentor和盲花蜱属Aponomma)。根据新的分类变更对已知种类进行了分析。至2006年,世界已知蜱类有3科18属897种,中国有2科10属119种。阐明了有关蜱类系统发育研究的主要观点,并讨论了其不足和有待深入研究的问题。目前,把形态学和分子生物学数据结合在一起的全证据方法,并结合蜱类和不同宿主之间的关系、动物地理学、古生物学以及比较寄生虫学的资料,成为解决蜱类系统发育问题的有效途径。  相似文献   

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昆虫病原索科线虫是一类宝贵的昆虫天敌资源,对农、林及卫生害虫的综合治理、环境保护以及实现农田生物多样性,都具有重要的学术和实用价值。其分子系统学研究涉及RAPD技术、SAFLP技术和基因分子标记技术对索科线虫种属间的亲缘关系探究,以及其线粒体全基因组分析等。  相似文献   

10.
蜘蛛是地球上最古老和物种最丰富的生物类群之一,有化石记录最早可追溯至泥盆纪(距今约三亿八百万年).对蜘蛛的系统学研究长期以传统的形态分类为主,随着分子生物学技术的发展,蜘蛛分子系统学研究也取得了长足进展:部分类群依据分子数据或分子结合形态的系统发育关系得以解决,并建立了相应的系统发育树; 所选择的分子标记除来自于线粒体DNA外(如:COI、12S rDNA和16S rDNA等)还有核DNA(如:18S rDNA、28S rDNA和Hitone 3等); 最新的分析方法和分析软件也得到运用.这些工作为蜘蛛的生命之树研究奠定了重要基础.本文对蜘蛛分子系统学研究所涉及到的问题进行了分析讨论,以期为蜘蛛分子系统学的深入开展提供基础资料.  相似文献   

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Actinidia (Actinidiaceae) is of economic importance for its edible fruits.Traditional taxonomy divided the genus into four sections,Leiocarpae Dunn,Maculatae Dunn,Strigosae Li,and Stellatae Li.However,phylogenetic studies based on morphology and molecular markers have posed challenges to the four-section scheme.It appears that the natural classification of the genus points to the existence of two groups,one comprising Leiocarpae,and the other Maculatae,Strigosae,and Stellatae.Single- or low-copy genes would probably be useful in untangling the perplexity andthe reticulate evolution of the genus.However,any phylogenetic studies must be firmly based on sound taxonomy and identification.Population sampling throughout the distribution range of the taxa should be carried out in order to study the variation pattern of the morphology and,ultimately,to clarify the confusion existing in some taxa.A combination of morphometrics and molecular data is highly desirable for resolving the uncertainty in Actinidia taxonomy.  相似文献   

13.
Several ways in which morphology is used in systematic and evolutionary research in angiosperms are shown and illustrated with examples: 1) searches for special structural similarities, which can be used to find hints for hitherto unrecognized relationships in groups with unresolved phylogenetic position; 2) cladistic studies based on morphology and combined morphological and molecular analyses; 3) comparative morphological studies in new, morphologically puzzling clades derived from molecular studies; 4) studies of morphological character evolution, unusual evolutionary directions, and evolutionary lability based on molecular studies; and 5) studies of organ evolution. Conclusions: Goals of comparative morphology have shifted in the present molecular era. Morphology no longer plays the primary role in phylogenetic studies. However, new opportunities for morphology are opening up that were not present in the premolecular era: 1) phylogenetic studies with combined molecular and morphological analyses; 2) reconstruction of the evolution of morphological features based on molecularly derived cladograms; 3) refined analysis of morphological features induced by inconsistencies of previous molecular and molecular phylogenetic analyses; 4) better understanding of morphological features by judgment in a wider biological context; 5) increased potential for including fossils in morphological analyses; and 6) exploration of the evolution of morphological traits by integration of comparative structural and molecular developmental genetic aspects (Evo-Devo); this field is still in its infancy in botany; its advancement is one of the major goals of evolutionary botany.  相似文献   

14.
蓝藻的分子系统学研究   总被引:1,自引:0,他引:1  
藻类分子系统学是一门新兴的学科。介绍了蓝藻分子系统学的发展、定义和蓝藻分子系统学的研究方法,并举例说明了各种方法的应用。同时,对蓝藻分子系统学发展前景作出了展望。  相似文献   

15.
The molecular architecture of the TNF superfamily.   总被引:31,自引:0,他引:31  
Ligands of the TNF (tumour necrosis factor) superfamily have pivotal roles in the organization and function of the immune system, and are implicated in the aetiology of several acquired and genetic diseases. TNF ligands share a common structural motif, the TNF homology domain (THD), which binds to cysteine-rich domains (CRDs) of TNF receptors. CRDs are composed of structural modules, whose variation in number and type confers heterogeneity upon the family. Protein folds reminiscent of the THD and CRD are also found in other protein families, raising the possibility that the mode of interaction between TNF and TNF receptors might be conserved in other contexts.  相似文献   

16.
The ras superfamily of molecular switches   总被引:1,自引:0,他引:1  
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17.
Bayesian and parsimony phylogenetic analyses of sequence from two nuclear and two mitochondrial genes suggest that neither the molluscan superfamily Trochoidea, nor the family Turbinidae are monophyletic. The family Turbinidae s.l. divides into two main groups. The first group includes taxa previously referred to the five subfamilies Angariinae, Colloniinae, Phasianellinae, Tricoliinae, Gabrieloninae, and the liotiine genus Cinysca; these subfamilies are here recognized as Angariidae, Colloniidae, and Phasianellidae (with subfamilies Phasianellinae, Tricoliinae, and Gabrieloninae). The second group, which corresponds to Turbinidae sensu stricto, includes Prisogasterinae, Turbininae, and the liotiine genus Liotina, all of which are more closely related to trochids than they are to the first group. Several morphological studies have suggested previously that the family Phasianellidae is distinct from Turbinidae. However, this is the first study to suggest that Phasianellidae forms a group with some taxa previously thought of as turbinids, but excluding the nominotypical genus Turbo and its allies. The family Turbinidae has traditionally been described as the only family in the Vetigastropoda group that has a calcified operculum. The non-monophyly of Turbinidae suggests that calcareous opercula may have arisen independently more than once within the Vetigastropoda.  相似文献   

18.
Actinidia (Actinidiaceae) is of economic importance for its edible fruits. Traditional taxonomy divided the genus into four sections, Leiocarpae Dunn, Maculatae Dunn, Strigosae Li, and Stellatae Li. However, phylogenetic studies based on morphology and molecular markers have posed challenges to the four-section scheme. It appears that the natural classification of the genus points to the existence of two groups, one comprising Leiocarpae, and the other Maculatae, Strigosae, and Stellatae. Single- or low-copy genes would probably be useful in untangling the perplexity and the reticulate evolution of the genus. However, any phylogenetic studies must be firmly based on sound taxonomy and identification. Population sampling throughout the distribution range of the taxa should be carried out in order to study the variation pattern of the morphology and, ultimately, to clarify the confusion existing in some taxa. A combination of morphometrics and molecular data is highly desirable for resolving the uncertainty in Actinidia taxonomy.  相似文献   

19.
双翅目昆虫分为长角亚目和短角亚目,前者主要类群包括蚊、蠓、蛉和蚋,后者主要类群为虻类和蝇类。国内外学者对双翅目昆虫形态分类和分子系统发育关系研究均较多。本文整理总结了几种主要核基因在双翅目昆虫进化和系统发育关系的研究资料,结果显示:双翅目的单系性得到了众多形态学、生物学和分子数据的支持,多数系统发育研究认为传统的长角亚目为并系,短角亚目是一个单系,其主要类群舞虻下目、环裂类、有缝组和有瓣蝇类均为单系,但非环裂类、无缝组为并系,无瓣类可能为并系;基本搞清了有重要医学意义和与环境关系密切的类群,特别是有瓣蝇类各科类群分类系统的进化关系;双翅目昆虫发生辐射进化的三个分支节点时间即:低等双翅目(蚊类)2.2亿年、低等短角亚目(虻类)1.8亿年、有缝组(蝇类)6500万年;大量双翅目昆虫自然生命史历经吸血性、植食性和寄生性,有2.6亿年以上的演化历程。从相关核基因研究中总结出:18SrRNA、28SrRNA和CAD基因能很好的解决高级阶元从目到属的系统发育问题;EF-1ɑ基因和White基因更适合从科到属水平的分类阶元;ITS基因一般应用在从属到种水平的低级分类阶元,并被广泛应用到双翅目昆虫分子系统学研究中。  相似文献   

20.
Dobzhansky stated that nothing in biology makes sense except in the light of evolution. A close corollary, and the central theme of this paper, is that everything makes a lot more sense in the light of phylogeny. Systematics is in the midst of a renaissance, heralded by the widespread application of new analytical approaches and the introduction of molecular techniques. Molecular phylogenetic analyses are now commonplace, and they have provided unparalleled insights into relationships at all levels of plant phylogeny. At deep levels, molecular studies have revealed that charophyte green algae are the closest relatives of the land plants and suggested that liverworts are sister to all other extant land plants. Other studies have suggested that lycopods are sister to all other vascular plants and clarified relationships among the ferns. The impact of molecular phylogenetics on the angiosperms has been particularly dramatic – some of the largest phylogenetic analyses yet conducted have involved the angiosperms. Inferences from three genes (rbcL, atpB, 18S rDNA) agree in the major features of angiosperm phylogeny and have resulted in a reclassification of the angiosperms. This ordinal-level reclassification is perhaps the most dramatic and important change in higher-level angiosperm taxonomy in the past 200 years. At lower taxonomic levels, phylogenetic analyses have revealed the closest relatives of many crops and model organisms for studies of molecular genetics, concomitantly pointing to possible relatives for use in comparative studies and plant breeding. Furthermore, phylogenetic information has contributed to new perspectives on the evolution of polyploid genomes. The phylogenetic trees now available at all levels of the taxonomic hierarchy for angiosperms and other green plants should play a pivotal role in comparative studies in diverse fields from ecology to molecular evolution and comparative genetics.  相似文献   

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