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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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1981年,美国加利福尼亚大学Riverside分校的迈克尔·克莱格MichaelClegg博士利用他的休假期到澳大利亚堪培拉CSIRO的一个实验室访问,并提出了一项研究计划,即利用叶绿体DNA的RFLP分析探讨现代和古代大麦栽培型之间的关系。与克莱格在同一个实验室作访问学者的杰拉德·佐拉斯基(GerardZurawski)也来自加州,他刚刚完成了对菠菜的rbcL基因测序,而下一个材料是豌豆。在非常偶然的一次谈话中,佐拉斯基向克莱格建议:“RFLP分析固然不错,但何不尝试比较一下大麦叶绿体基… 相似文献
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RAPD分子标记在园艺植物遗传学研究中的应用 总被引:6,自引:2,他引:6
1971年Khorana等提出多聚链式反应 (PolymeraseChainRe action ,PCR)的基本概念之后 ,1985年Saiki等阐述了具体原理和作法 ,并在 1988年从细菌中发现了热稳定性的TaqDNA聚合酶 ,从而实现了PCR反应的自动化。在PCR技术的基础上 ,Williams等[1 ] 1990年采用随机核苷酸序列为引物扩增基因组DNA的随机片段 ,产生了一种新的分子标记———随机扩增多态性DNA (RandomAmplifiedPolymorphicDNA) ,简称RAPD ,即以一个寡聚核苷酸序列 (通常为 10碱基 )为引物 ,对基因组DNA随机扩增 ,从而得到多态性图谱作为遗传标记的方法。同年Welsh… 相似文献
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地黄属分子系统学分析 总被引:4,自引:0,他引:4
地黄属是中国准特有属,属内种间关系仍待澄清。该研究基于多个个体的叶绿体与核基因片段对地黄属进行系统发育重建,探讨属内物种分化与可能历史。结果表明:(1)地黄属为单系群,天目地黄为本属原始类群,并与湖北地黄互为姐妹群或连续姐妹群,裂叶地黄-高地黄、地黄-茄叶地黄分别组成姐妹群;(2)多个个体构建的系统树更能揭示本属物种关系的复杂性;(3)祖先分布区重建表明本属经历过3次扩张与2次隔离过程,物种形成过程与历史气候变化密切相关。最后该研究提出了地黄属物种形成研究亟待解决的几个重要问题。 相似文献
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植物反转录转座子及其分子标记 总被引:10,自引:0,他引:10
反转录转座子(retrotransposon)是真核生物中一类可移动因子,可分为m反转录转座子和非LTR反转录转座子。反转录转座子以高拷贝在植物界广泛分布,可以通过纵向和横向分别在世代之间和不同种之间进行传递,同一家族的反转录转座子具有高度的异质性.在一些生物的和非生物的逆境条件下,反转录转座子的转录可以被激活。由于反转录转座子的特点,使其作为一种分子标记得以应用。SSAP、IRAP、REMAP和RBIP等分子标记相继发展起来,在基因作图、生物遗传多样性与系统进化、品种鉴定等方面具有广泛的应用前景。 相似文献
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结合同工酶分析技术及随机扩增多态性DNA(RAPD)、限制性片段长度多态性(RFLP)和DNA序列测序3种分子生物学技术,对苔藓植物的分子系统学研究概况进行了介绍,并指出了在苔藓植物分子系统学研究中存在的一些问题。 相似文献
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苔藓植物分子系统学研究概况 总被引:1,自引:0,他引:1
结合同工酶分析技术及随机扩增多态性DNA(RAPD)、限制性片段长度多态性(RFLP)和DNA序列测序3种分子生物学技术,对苔藓植物的分子系统学研究概况进行了介绍,并指出了在苔藓植物分子系统学研究中存在的一些问题. 相似文献
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植物营养性状有关基因的分子标记及定位 总被引:7,自引:0,他引:7
养分逆境是世界范围内中低产田的主要限制因素之一,如酸性土壤的低有效磷、铝毒,石灰性土壤铁锌的缺乏等等。耕作制度和增加化肥投入是生产上最主要的矫正措施。对于经济落后、资源缺乏国家而言,经济有效的战略措施之一是发展低投入农业生产途径,依靠选育优良品种,使之具有适应土壤环境逆境及养分高效吸收利用的特性。大量研究表明,作物各种元素胁迫的反应程度存在基因型差异^[1],这为筛选和培育养分高效吸收利用的作物良 相似文献
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Grechko VV 《Genetika》2002,38(8):1013-1033
The review considers data on the use of the main evolutionary markers (ribosomal, mitochondrial, and RAPD markers; dispersed and tandem repeats). Some circumstances impending analysis of these data are discussed. 相似文献
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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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J. W. Wägele 《Journal of Zoological Systematics and Evolutionary Research》1995,33(3-4):42-47
A review of the fundamental difference between single molecular-sequence positions, or numerical characters, and complex morphological characters is the subject of this study. It has been found that transformation series of single complex structures contain enough information to allow a priori determination of character order and that rooting of a dendrogram is possible without out-group comparison, while trees based on less-informative characters can usually only be rooted with out-group comparison. Furthermore, the quality of total information used is decisive in discriminating between hypotheses of relationships. Numerical methods for the inference of phylogenies have been found to be useful for high numbers of characters that have only a low information content, while the Hennigian procedure seems to be preferable for complex characters.
Ein fundamentaler Unterschied zwischen der einzelnen Sequenzposition oder auch numerischen Merkmalen und komplexen morphologischen Merkmalen ist ihr Informationsgehalt. Merkmalsreihen komplexer Strukturen enthalten meist genügend Information, um a priori die Bestimmung der Lesrichtung zu ermöglichen. Die Feststellung des Ursprunges eines Dendrogramms ist somit ohne kladistischen Außengruppenvergleich möglich, während Bäume (Topologien), die auf wenig informativen Merkmalen beruhen, allgemein nur mit dem kladistischen Außengruppenvergleich 'gewurzelt' werden können. Die Qualität der insgesamt verwendeten Information ist entscheidend für die Wahl zwischen alternativen Verwandtschaftshypothesen. Numerische Methoden der Rekonstruktion der Phylogenese sind nützlich bei Verwendung einer gro β en Zahl informationsarmer Merkmale; das Hennigsche Verfahren ist für komplexe Merkmale vorzuziehen. 相似文献
Zusammenfassung
Ein fundamentaler Unterschied zwischen der einzelnen Sequenzposition oder auch numerischen Merkmalen und komplexen morphologischen Merkmalen ist ihr Informationsgehalt. Merkmalsreihen komplexer Strukturen enthalten meist genügend Information, um a priori die Bestimmung der Lesrichtung zu ermöglichen. Die Feststellung des Ursprunges eines Dendrogramms ist somit ohne kladistischen Außengruppenvergleich möglich, während Bäume (Topologien), die auf wenig informativen Merkmalen beruhen, allgemein nur mit dem kladistischen Außengruppenvergleich 'gewurzelt' werden können. Die Qualität der insgesamt verwendeten Information ist entscheidend für die Wahl zwischen alternativen Verwandtschaftshypothesen. Numerische Methoden der Rekonstruktion der Phylogenese sind nützlich bei Verwendung einer gro β en Zahl informationsarmer Merkmale; das Hennigsche Verfahren ist für komplexe Merkmale vorzuziehen. 相似文献
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On the information content of characters in comparative morphology and molecular systematics 总被引:1,自引:0,他引:1
A review of the fundamental difference between single molecular-sequence positions, or numerical characters, and complex morphological characters is the subject of this study. It has been found that transformation series of single complex structures contain enough information to allow a priori determination of character order and that rooting of a dendrogram is possible without out-group comparison, while trees based on less-informative characters can usually only be rooted with out-group comparison. Furthermore, the quality of total information used is decisive in discriminating between hypotheses of relationships. Numerical methods for the inference of phylogenies have been found to be useful for high numbers of characters that have only a low information content, while the Hennigian procedure seems to be preferable for complex characters. 相似文献
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Although the matK gene has been used in addressing systematic questions in four families, its potential application to plant systematics above the family level has not been investigated. This paper examines the rates, patterns, and types of nucleotide substitutions in the gene and addresses its utility in constructing phylogenies above the family level. Eleven complete sequences from the GenBank representing seed plants and liverworts and nine partial sequences generated for genera representing the monocot families Poaceae, Joinvilleaceae, Cyperaceae, and Smilacaceae were analyzed. The study underscored the high rate of substitution in the gene and the presence of mutationally conserved sectors. The use of different sectors of the gene and the cumulative inclusion of informative sites showed that the 3' region was most useful in resolving phylogeny, and that the topology and robustness of the tree reached a plateau after the inclusion of 100 informative sites from that region for the taxa used. The impact of using partial sequencing on sample size is addressed. The presence of a relatively conserved 3' region and the less conserved 5' region provides two sets of characters that can be used at different taxonomic levels from the tribal to the division levels. 相似文献
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核糖体DNA ITS区序列在植物分子系统学研究中的价值 总被引:19,自引:0,他引:19
本文就近年来国内外有关被子植物核糖体DNA中的内转录间隔区(ITS)序列在植物属内,近缘属间乃至科内系统发育研究中的应用,结合作者在中国姜科山姜属(Alpinia Roxb.)上的研究,对ITS区序列在植物分子系统学研究中的价值作一简要综述,对其应用前景也进行了讨论。 相似文献
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Toru Terachi 《Journal of plant research》1993,106(1):75-79
Recent advances in manipulating nucleic acids have opened a new research field called plant molecular systematics. This short
review provides an overview of molecular techniques which have been used in the analysis of DNA molecules for the study of
plant systematics, with a special emphasis on PCR. The early application of DNA analysis, DNA/DNA hybridization, has not become
popular with plant systematists, because of several disadvantages inherent in the method. The survey of restriction fragment
length polymorphisms (RFLPs), on the contrary, has become one of the preferred methods used by plant molecular systematists,
since the method is relatively easy to perform. Although unambiguous data can be obtained by both long-range restriction mapping
and nucleotide sequencing, these approaches may have limited use in plant molecular systematics because of their laborious
experimental procedures relying on conventional molecular cloning techniques. To date, PCR based analyses of the DNA molecule
seem to be the most suitable experimental approach for plant molecular systematics. Several advantages of the method have
changed both the quality and quantity of the DNA data. Further application of PCR to plant molecular systematics will open
up a new era in the field.
The present paper is based on the contribution which was read in a symposium entitled “Organellar DNA Variations in Higher
Plants and their Taxonomic Significance”, at the 50th Annual Meeting of the Botanical Society of Japan in Shizuoka on October
2, 1990, under the auspices of the Japan Society of Plant Taxonomists. 相似文献
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The Southern Ocean is surprisingly rich in species that coexist in one of the most extreme environments on Earth yet the processes
leading to speciation in this ecosystem are not well understood. To remedy this, tools that measure the genetic connectedness
within a species are needed. Although useful for phylogenetic purposes, the readily available mitochondrial markers (e.g.
16S, COI) suffer from numerous shortcomings for population genetics. Therefore, molecular markers are needed that are sufficiently
variable, unlinked, biparentally inherited, and distributed over the whole genome. We argue that microsatellites are suitable
markers that have not been widely used in exploratory studies due to their difficult initial set-up. Working with the Ceratoserolis trilobitoides species complex (Isopoda), we demonstrate that using a novel protocol many microsatellites can be identified quickly. An
increased availability of these highly sensitive markers will be useful for studies addressing the origin of species in the
Southern Ocean and their response to future climate change.
Christoph Held and Florian Leese contributed equally to this paper. 相似文献
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Pollen and anther characters are potentially informative in higher-level systematics of monocotyledons. Several characters of monocot pollen and anthers (tapetum type, microsporogenesis type and inaperturate pollen) are reviewed here in relation to recent phylogenetic concepts of the group, and new data are presented for some critical taxa. The first-branching monocotyledon, Acorus , has a secretory tapetum but most other early branching taxa (i.e., most Alismatales, except Tofieldia ) are plasmodial. The lilioid orders, Pandanales, Dioscoreales, Liliales and Asparagales are almost uniformly secretory. The tapetum is more diverse within the commelinoid clade. Successive microsporogenesis predominates in the monocotyledons although the simultaneous type is of systematic significance within some orders, such as Dioscoreales,Asparagales and Poales. Inaperturate pollen (either "functionally monoaperturate" or "omniaperturate") occurs in every major monocot group. It predominates in Alismatales and Zingiberales, and is a synapomorphy for some Liliales and Asparagales. 相似文献