大趾鼠耳蝠线粒体DNA控制区结构及变异

采用PCR产物直接测序法首次测定大趾鼠耳蝠(Myotis macrodactylus)10个个体的线粒体DNA(mtDNA)控制区全序列,并进行了结构和变异分析。结果表明,大趾鼠耳蝠的控制区结构与其他哺乳动物相似,可分为一个中央保守区(包括F、E、D、C、B元件)和两个外围结构域:延伸的终止结合序列区(包括ETAS1和ETAS2元件)和保守序列区(包括CSB1、CSB2和CSB3元件),其中最为保守的是中央保守区(核苷酸变异度为1.8%)。大趾鼠耳蝠控制区核苷酸全序列具有丰富的长度多态性(1778～2048bp),主要是由在碱基组成、重复数目和排列方式上异质的串联重复序列造成的。在ETAS内发现了TACAT及其反向互补序列ATGTA,支持滑移错配模式(slipped mispairing model)。本研究为该物种的进一步研究和保护提供基础遗传数据。     

松江鲈线粒体DNA控制区结构和遗传多样性分析

为探讨松江鲈(Trachidermus fasciatus Heckel)线粒体控制区特征及其群体遗传结构, 研究测定分析了中国和日本沿海共8个群体的线粒体控制区序列, 分析了其结构特征, 识别出终止序列区(ETAS)、中央保守区(CD)和保守序列区(CSB)的特征序列。遗传多样性分析结果显示: 69个松江鲈个体共检测到47个单倍型, 呈现出核苷酸多样性(0.0079)较低和单倍型多样性(0.978)较高的特点。单倍型邻接关系树和单倍型网络关系图均显示松江鲈分为中国和日本两大世系。遗传分化系数(Fst)和分子方差分析(AMOVA)结果表明, 松江鲈中国群体和日本群体之间存在的遗传差异较显著, 中国沿海各群体之间亦存在着一定程度的遗传差异, 该分化主要由历史环境变动、当代环境因素和自身生态习性等原因造成。     

尾斑瘰螈种群的D-loop区遗传多样性分析

以线粒体DNA D-loop序列为分子标记,研究了采自雷公山和武陵山的尾斑瘰螈(Paramesotriton caudopunclatus)5个种群的遗传多样性.获得42个个体mtDNA D-loop区序列,长度为690 bp,其中有30个变异位点,由此定义了13个单倍型.5个种群中未出现共享单倍型的现象.尾斑瘰螈种群...     

都柳江鲤、鲫和草鱼种群mtDNA控制区及遗传多样性分析

采用PCR和DNA测序技术对贵州都柳江鲤(Cyprinus carpio)、鲫(Carassius auratus)和草鱼(Ctenopharyngodon idellus)种群的mtDNA控制区序列及遗传多样性进行了研究。获得了都柳江鲤、鲫和草鱼mtDNA控制区长度分别为899~901 bp、787 bp和901~905 bp的序列。该3种鱼类控制区碱基A、T含量较高,G含量最低。识别了该3种鱼类mtDNA控制区终止序列区、中央保守区和保守序列区等保守序列。其中,除CSB-2和CSB-3碱基组成相同外,其余核心序列碱基组成存在着差异。都柳江鲤、鲫和草鱼种群mtDNA控制区分别有24、24和11个多态位点,分属12、17和8个单倍型。都柳江鲤、鲫种群遗传多样性较高,草鱼种群遗传多样性较低。因此,有必要开展都柳江草鱼种群遗传多样性的保护。     

基于D-loop区部分序列分析黔、陕、湘3个大鲵种群系统发育关系和遗传分化

为弄清贵州大鲵群体与中国其他大鲵群体的遗传关系,探究贵州大鲵种群遗传背景,本研究测定了贵州、陕西、湖南共82条大鲵的mt DNA D-loop区部分序列,进行系统发育关系和遗传分化的分析。结果显示:82条序列中共检出7种单倍型序列,贵州大鲵群体有6个单倍型、陕西群体3个单倍型、湖南群体只有1个单倍型。综合动物遗传多样性指数,得出遗传多样性水平依次排序为贵州陕西湖南,但均处于低水平遗传多样性的状态。由于地理隔离的原因,种群间基因流Nm1,遗传分化显著,但没有达到种群分化的水平。贵州种群与湖南种群在14~35万年前发生分歧,与陕西种群在12~30万年前发生遗传分歧;陕西与湖南种群发生分歧的时间则短得多,约在2~5万年前。贵州大鲵种群中可能出现隐种。     

基于cpDNA atpB-rbcL非编码序列分析桫椤种群遗传结构和遗传多样性,以贵州赤水桫椤国家级自然保护区为例

以PCR产物克隆后测序的方法测定了贵州赤水桫椤国家级自然保护区3个种群59个个体的叶绿体DNA (cpDNA) atpB-rbcL非编码区序列.序列长度介于727~732 bp之间,具长度多态性,A+T百分比含量较高,介于63.27%~63.89%之间.遗传多样性水平较低,表现出较高的单倍型多样性(h=0.639)和低的核苷酸多样性(Dij=0.00028)并存的特征,提示现有种群可能源自一个有效群体规模较小的种群的快速扩张,扩张时间尚短,不足以形成更为复杂的遗传结构.种群间的高基因流Nm、低遗传分化度FST、AMOVA分析以及DNA歧异度结果一致显示各种群间无明显的遗传分化.     

褐马鸡圈养种群的mtDNA控制区多态性

褐马鸡(Crossoptilon mantchuricum)是我国特有的濒危鸟类,国家一级保护动物。为了保护褐马鸡的种质资源,从分子水平上评价褐马鸡的遗传多样性,对山西省庞泉沟自然保护区、太原市动物园的褐马鸡种群20个个体,线粒体DNA D-loop区全序列进行了克隆和测定,使用Clustal X、DnaSP4.0、Mega3.1等生物信息学软件,对全部20条序列开展了比对分析,确定了多态位点与单倍型数目,计算了核苷酸多样性和单倍型多样性;比较了两个种群的遗传变异,初步探讨了褐马鸡种群的遗传多样性和遗传结构。结果表明:20条褐马鸡线粒体DNA D-loop区全序列长度在1236 1237bp之间,其中A、T、G和C 4种核苷酸的平均含量分别为31.0%、26.8%、27.5%和14.8%,A+T含量(57.8%)高于G+C含量(42.3%)。排除1处核苷酸的插入或缺失后,共检测出26个突变位点,占分析序列总长度的2.1%,其中包括25处单一多态位点和1处简约信息位点。20个个体检测出13个单倍型,其中11个个体具有独特的单倍型,2个共享单倍型。褐马鸡两个种群的单倍型多样性(h)为0.911 0.933,核苷酸多样性(π)为0.002 0.003,单倍型间的遗传距离为0.003 0.002。根据单倍型构建了褐马鸡两个种群的NJ分子系统树。聚类表明,2个种群的个体并没有按相应的地理位置进行聚类。揭示褐马鸡具有较高的单倍型多样性和较低的核苷酸多样性,种群的遗传变异较低;两个种群单倍型间的遗传距离较近,遗传多样性参数接近,统计分析无显著差异,两个种群尚未表现出明显的遗传分化,且两个种群间有基因流存在。     

鱇[鱼良]白鱼线粒体DNA控制区结构和种群遗传多样性分析

用特异性引物对鱇(鱼良)白鱼(Anabarilius grahami)DNA进行PCR扩增,获得了鱇(鱼良)白鱼线粒体DNA控制区基冈全序列(930bp).控制区T、C、A和G碱基组成为29.8%、22.5%、33.0和14.7%.对照其他已报道的鱼类控制区结构,对鱇(鱼良)白鱼控制区结构进行了分析,识别了其终止序列区、中央保守区和保守序列区,找到了终止相关的序列TAS以及保守序列(CSB-F、CSB-D、CSB-1、CSB-2、CSB-3).同时运用DNA分析软件对鱇(鱼良)白鱼一个驯养种群(中国科学院昆明动物研究所珍稀鱼类繁育中心)及两个自然地理种群(江川县明星鱼洞、江川县牛摩村)进行了遗传多样性分析.结果显示:两个自然种群存在较强基因交流,未出现遗传分化;人工驯养种群遗传多样性最高,种群复壮程度较好.     

罗非鱼mtDNA D-loop区部分序列结构和种群遗传多样性分析

采用PCR扩增和测序的方法获得了尼罗罗非鱼(Oreochromis niloticus)埃及品系(简称AJ,22尾)、88品系(简称XH,26尾)和奥利亚罗非鱼(O.aureus)(简称ALY,28尾)"夏奥1号"线粒体DNA控制区(mtDNA D-loop)的部分序列(575～581 bp)。对照其他已报道的鱼类控制区结构,对序列结构进行分析,成功识别了罗非鱼mtDNA D-loop区序列的中央保守区和保守序列区,找到了4个特征序列(CSB-D、CSB1、CSB2、CSB3)。76个个体共检测出28个单倍型。AJ群体有12个单倍型,XH群体有10个单倍型,ALY群体存在9个单倍型。其中,3个群体共享1个单倍型(XH06),AJ和XH群体共享一个单倍型(XH10),其他为各个群体独有。AJ和XH(Nm=0.77)、AJ和ALY(Nm=0.02)、XH和ALY(Nm=0.02)之间均存在一定的遗传分化。AJ和XH的核苷酸多态性(Pi)值(分别为0.042 4、0.031 1)明显高于ALY的Pi值(0.001 2)。本实验中的ALY品种纯度高,AJ和XH的遗传多样性较丰富。mtDNA D-loop区能反映出罗非鱼群体的种质特征,适用于罗非鱼群体内的遗传多样性研究。     

淮河野生鲇鱼线粒体Cyt b基因的序列变异与遗传结构分析

本研究利用线粒体DNA细胞色素b(Cyt b)基因序列分析淮河信阳段、淮滨段、蚌埠段、洪泽湖及其支流颍河、淠河和池河的野生鲇鱼(Silurus asotus)种群遗传结构及种群历史.结果表明,在841 bp的同源序列中,7个种群共检测到变异位点40个,占全部序列的4.76％,121个个体共检测到32种单倍型;7个种群的平均单倍型多样性(h)、核甘酸多样性(Pi)分别为0.884 8、0.003 8,表明淮河野生鲇鱼种群的遗传多样性水平较高.7个种群间的遗传分化指数Fst为0.115 0,仅12.92％的变异来自种群间(AMOVA分析),基因交流值为3.85,种群间K2-P遗传距离为0.002 ～0.009,显示鲇鱼种群间没有发生明显的地理分化.NJ树揭示7个种群的个体组成2个谱系,但这2个谱系与地理分布并不相关.中性检验、错配分析和Network网络亲缘关系分析皆表明鲇鱼种群有过种群扩张,扩张时间约在0.17～0.29百万年前的中更新世中期和末期.     

白鱼线粒体DNA控制区结构和种群遗传多样性分析

用特异性引物对白鱼(Anabarilius grahami)DNA进行PCR扩增,获得了白鱼线粒体DNA控制区基因全序列(930bp)。控制区T、C、A和G碱基组成为29.8%、22.5%、33.0%和14.7%。对照其他已报道的鱼类控制区结构,对白鱼控制区结构进行了分析,识别了其终止序列区、中央保守区和保守序列区,找到了终止相关的序列TAS以及保守序列(CSB-F、CSB-D、CSB-1、CSB-2、CSB-3)。同时运用DNA分析软件对白鱼一个驯养种群(中国科学院昆明动物研究所珍稀鱼类繁育中心)及两个自然地理种群(江川县明星鱼洞、江川县牛摩村)进行了遗传多样性分析。结果显示:两个自然种群存在较强基因交流,未出现遗传分化;人工驯养种群遗传多样性最高,种群复壮程度较好。     

白鱼线粒体DNA控制区结构和种群遗传多样性分析

用特异性引物对白鱼（Anabarilius grahami）DNA进行PCR扩增,获得了白鱼线粒体DNA控制区基因全序列（930 bp）。控制区T、C、A和G碱基组成为29.8%、22.5%、33.0%和14.7%。对照其他已报道的鱼类控制区结构,对白鱼控制区结构进行了分析,识别了其终止序列区、中央保守区和保守序列区,找到了终止相关的序列TAS以及保守序列（CSB-F、CSB-D、CSB-1、CSB-2、CSB-3）。同时运用DNA分析软件对白鱼一个驯养种群（中国科学院昆明动物研究所珍稀鱼类繁育中心）及两个自然地理种群（江川县明星鱼洞、江川县牛摩村）进行了遗传多样性分析。结果显示：两个自然种群存在较强基因交流,未出现遗传分化;人工驯养种群遗传多样性最高,种群复壮程度较好。     

DNA sequence variation in the mitochondrial control region of subterranean mole rats,Spalax ehrenbergi superspecies,in Israel

The complete mitochondrial control region was sequenced for 60 individuals representing different populations for each of the four species of the subterranean mole rat Spalax ehrenbergi superspecies in Israel: Spalax galili (2n = 52), S. golani (2n = 54), S. carmeli (2n = 58), and S. judaei (2n = 60). The control region of all species and populations is very similar both in length (979 to 983 bp) and in base composition. As in agreement with previous surveys on mitochondrial control regions on mammals, the mole rat control region can be divided into a central domain and two flanking domains, ETAS (extended termination associated sequences) and CSB (conserved sequence blocks). Along with the common conserved blocks found in these domains (ETAS1, ETAS2, CSB1, CSB2, and CSB3), we have also detected in all individuals an ETAS1-like and a CSB1-like element, both in the ETAS domain. The most conserved region was the central domain, followed by the CSB and ETAS domains, showing important differences in the four species analyzed. Phylogenetic analysis supported the existence of two clades. One clade contained individuals belonging to Spalax galili (2n = 52) and S. golani (2n = 54), separated in two different branches depending on the species. The other clade contained individuals belonging to S. carmeli (2n = 58) and S. judaei (2n = 60) mixed together, suggesting a more recent event of speciation. Within species we have observed a southward trend of increasing variability. These results have been explained as a consequence of the adaptation of the species to ecological factors such as aridity and temperature stresses.     

Lineage Specificity of the Evolutionary Dynamics of the mtDNA D-Loop Region in Rodents

This paper reports an intraorder study on the D-loop-containing region of the mitochondrial DNA in rodents. A complete multialignment of this region is not feasible with the exception of some conserved regions. The comparative analysis of 25 complete rodent sequences from 23 species plus one lagomorph has revealed that only the central domain (CD), a conserved region of about 80 bp in the extended termination-associated sequences (ETAS) domain, adjacent to the CD, the ETAS1, and conserved sequence block (CSB) 1 blocks are present in all rodent species, whereas the presence of CSB2 and CSB3 is erratic within the order. We have also found a conserved region of 90 bp located between tRNAPro and ETAS1 present in fat dormouse, squirrel, guinea pig, and rabbit. Repeated sequences are present in both the ETAS and the CSB domain, but the repeats differ in length, copy number, and base composition in different species. The potential use of the D-loop for evolutionary studies has been investigated; the presence/absence of conserved blocks and/or repeated sequences cannot be used as a reliable phylogenetic marker, since in some cases they may be shared by distantly related organisms but not by close ones, while in other ones a relationship between tree topology and presence/absence of such motifs is observed. Better results can be obtained by the use of the CD, which, however, due to its reduced size, when used for tracing a phylogenetic tree, shows some nodes with low statistical support. Received: 26 February 2001 / Accepted: 6 June 2001     

DNA sequence variation in the mitochondrial control region of red-backed voles (Clethrionomys)

The complete mitochondrial DNA (mtDNA) control region was sequenced for 71 individuals from five species of the rodent genus Clethrionomys both to understand patterns of variation and to explore the existence of previously described domains and other elements. Among species, the control region ranged from 942 to 971 bp in length. Our data were compatible with the proposal of three domains (extended terminal associated sequences [ETAS], central, conserved sequence blocks [CSB]) within the control region. The most conserved region in the control region was the central domain (12% of nucleotide positions variable), whereas in the ETAS and CSB domains, 22% and 40% of nucleotide positions were variable, respectively. Tandem repeats were encountered only in the ETAS domain of Clethrionomys rufocanus. This tandem repeat found in C. rufocanus was 24 bp in length and was located at the 5' end of the control region. Only two of the proposed CSB and ETAS elements appeared to be supported by our data; however, a "CSB1-like" element was also documented in the ETAS domain.     

Structure,DNA sequence variation and phylogenetic implications of the mitochondrial control region in horseshoe bats

There have been few studies of the structural and evolutionary characteristics of the mitochondrial control region (CR) in rhinolophids, yet this could have important consequences for the interpretation of phylogenetic relationships within this group. Here we sequenced and analyzed the CR of 37 individuals from 12 Rhinolophus species, including 2 species from GenBank. The length of the CR ranged from 1335 to 1514 bp, and the base composition was very similar among species. The CR of horseshoe bats, like that of other mammals, could be subdivided into a central conserved domain (CD) and two flanking variable domains, extended termination associated sequences (ETAS), and conserved sequence blocks (CSB). Besides the common conserved blocks (ETAS1, ETAS2, F-B boxes, CSB1, CSB2 and CSB3) found in 3 domains, an ETAS2-like and a CSB1-like element were also detected in the ETAS and CSB domains, respectively, in all individuals. Notwithstanding a short tandem repeat (11 or 13 bp) between CSB1 and CSB2 in all specimens, the base composition, copy number and arrays are all variable. A long tandem repeat (79 bp) was only identified in the ETAS domain in one individual of R. pusillus. Phylogenetic reconstructions based on the CR sequences indicated that the molecular phylogenetic relationships among some Rhinolophus species were inconsistent with the results of phenetic analyses, but similar to phylogenetic constructions using cytochrome b. An unidentified species R. sp and 3 species from the philippinensis-group that were clearly morphologically different comprised a monophyletic group, which could have resulted from morphological independent evolution.     

Mitochondrial DNA sequence variations and systematics of the genus Distoechodon (Teleostei: Cyprinidae)

In the present paper, nucleotide sequences (925–929 bases) of the mitochondrial D-loop region and complete cytochrome b gene (1140 bases) were determined and analysed to investigate the systematic status of the genus Distoechodon . CSB1, CSB2, CSB3, CSB-D and ETAS were successfully identified in the D-loop region. The sequence variations among different samples suggest that Distoechodon compressus is a valid species and has its distribution in Taiwan, and that D. tumirostris multispinnis does not seem to be a valid species.     

鳜类鱼类的线粒体DNA控制区结构及其系统发育分析

鳜类为低等鲈形目鱼类,是东亚特有类群。然而,关于其系统位置、分类以及一些物种的有效性等尚有争议。采用PCR扩增直接测序的方法,获得了鳜、大眼鳜、斑鳜、暗鳜、波纹鳜、长体鳜、中国少鳞鳜线粒体DNA控制区基因的序列。对比其他已报道鱼类控制区的结构识别序列,对鳜类鱼类控制区的结构进行了分析,识别了终止序列区、中央保守区和保守序列区,并找到了DNA复制终止相关的序列ETAS和中央保守区的保守序列CSB-F、CSB-E、CSB-D以及保守序列区的保守序列CSB1、CSB2、CSB3。几种鳜鱼间共有191个变异位点,其中,终止序列区的变异最高,占总变异的61．3％,中央保守区和保守序列区占总变异的38．7％。这一结果可为全面了解鱼类线粒体DNA控制区的结构特征提供资料。同时,利用高度变异的控制区序列,以鲈科和错科作为外群,使用邻接法和最大简约法构建了这几种鳜鱼的系统发育树。结果表明：鳜类为一单系类群,鳜、大眼鳜、斑鳜、暗鳜、波纹鳜、长体鳜构成一支鳜鱼群,其中,鳜与大眼鳜为姐妹种;中国少鳞鳜为另一支少鳞鳜群;长体鳜未单独成一支,而是聚入鳜鱼群内,应更名为Siniperca roulei。研究结果支持将现生鳜类分为两个类群的观点。     

齐口裂腹鱼线粒体DNA控制区结构分析

利用直接测序法对齐口裂腹鱼(Schizothorax prenanti)线粒体DNA控制区进行了测序,并对其序列结构进行了分析.结果表明,齐口裂腹鱼线粒体控制区碱基组成中碱基A和T的含A明显高于G和C的含量,所有类型碱基组成中碱基G的含量最低,这与其他硬骨鱼类控制区碱基组成一致.通过与哺乳类和鲤形目鱼类控制区序列进行对...