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1.
栉孔扇贝16S rRNA基因片段序列的多态性研究 总被引：23，自引：7，他引：23
采用PCR技术扩增了栉孔扇贝（Chlamys farreri)线粒体DNA的16SrRNA基因片段，PCR产物经T载体连接之后进行了克隆，测序，得到634bp的核苷酸序列；分析了该片段的大连，烟台，青岛，朝鲜4个自然群体31个个体的核苷酸序列多态性，共检测到26个多态性核苷酸位点，18种单倍型，结果表明，4个群体中以朝鲜群体遗传多样性最高，其次为烟台，青岛群体，大连群体最低；不同自然分布区的栉孔扇贝未出现明显的遗传分化。 相似文献
2.
以烟台海域引发"绿潮"的浒苔为研究对象,采用PCR技术扩增出浒苔的ITS-1、5.8SrDNA及ITS-2片段,将扩增出的片段纯化后克隆至pGEM-TEasy载体,筛选阳性克隆进行序列测定。结果表明,浒苔的ITS-1序列长度为195bp,5.8S序列为155bp,ITS-2序列为181bp,该序列与浒苔属的多种物种ITS序列具有很高的同源性,在ITS-1区、5.8SrDNA区和ITS-2区仅存在4个转换/颠换位点。结合GenBank注册序列和本研究的结果发现,单纯依靠ITS序列并不能对浒苔属种类进行有效的分类鉴定。 相似文献
3.
长耳珠母贝核rRNA基因ITS-2序列分析 总被引：11，自引：0，他引：11
以相应引物聚合酶链式反应(PCR)扩增长耳珠母贝(Pinctada chemnitzi)核核糖体RNA基因第2转录间隔区(ITS-2),PCR产物大小约500bp,经克隆、测序,所得序列包含5．8S和28SrRNA基因部分序列和ITS-2全序列,4种碱基含量分别为27．11％(A)、24．95％(G)、21．26％(T)和26．68％(C)。5个克隆的DNA序列差异为0．0％-0．4％,不存在个体内变异。对其潜在应用进行了讨论。 相似文献
4.
For the population genetics analysis of the naturally grown brown seaweed Laminaria japonica (Laminariales,Phaeophyta) sampled from Dalian,Yantai,Weihai,Rongcheng and Qingdao in China,ten primers were employed to produce 88 bands as revealed by randomly amplified polymorphic DNA (RAPD) markers,and all these bands were polymorphic.According to these band patterns,there were 94 distinct phenotypes occurred in 100 samples indicating the high heterozygosity of this kelp.Dalian population samples showed the highest percentage of polymorphism (71.67%),and also the higher diversity estimated on the basis of the Shannon’s index (8.498),suggesting that this population could be chosen as the best resource for genetic breeding.The highest diversity of Yantai population possibly resulted from the introduction of L.longissima used for interspecific cross breeding with L.japonica cultivated in China.From Dalian southwards to Qingdao,the genetic variation of the five populations became less with a decrease in latitude,possibly due to the natural selection especially of high temperature.The genetic distance (Φ ST values) of the five populations was a little significantly correlated with the geographical distance (r=0.496) at P =0.05 by Mantel’s test.Weihai,Rongcheng and Yantai populations were closely grouped genetically together by Neighbor-joining cluster analysis probably in that the dispersal of the kelp by propagules more easily occurring in the range of relatively short distance.The analysis of molecular variance (AMOVA) also demonstrated that the relatively higher variation occurred among populations (71.49%) at an extremely significant level (P <0.000 1).All these evidence showed that there was a relatively distinct genetic differentiation among the sampled kelp populations,and L.japonica grown in China was also rather heterozygous in heredity. 相似文献
5.
应用AFLP标记技术对我国北方近海短蛸的遗传多样性进行分析。采用6对AFLP引物组合对4个群体(大连、烟台、青岛、连云港)120个个体进行扩增,其中每对引物扩增位点数在42—66之间,共得到303个扩增位点。4个群体内的多态位点比例为62.03%—67.93%。群体的Nei’s基因多样性指数(H)为0.2353—0.2617,Shannon多样性指数(I)为0.3497—0.3863,群体间的遗传距离为0.0497—0.085;大连群体的多态位点比例、Shannon多样性指数和群体Nei’s基因多样性指数均高于其它三个群体。用UPGMA方法构建的群体系统进化树显示,大连群体与烟台群体聚到一起,青岛群体与连云港群体聚到一起,显示群体间具有典型的地理特征,但群体间存在遗传渗透。分子变异分析(AMOVA)结果表明,短蛸群体88.28%的变异来源于群体内,群体间的变异占11.72%,显示短蛸的遗传变异主要来源于群体内个体间,但群体间已经有了一定程度的遗传分化。 相似文献
7.
基于线粒体DNA的COⅢ基因序列对我国沿海重要经济贝类紫贻贝3个养殖群体(烟台、乳山、东极)的遗传多样性和遗传结构进行了研究。由PCR扩增获得32个体的COⅢ基因750bp的部分序列,其多态性遗传参数统计显示,32个个体共检出18个单倍型,总群体单倍型多样性指数(Hd)为0.946,核苷酸多样性指数(Pi)为0.0207,平均核苷酸差异数(K)为15.316,三个群体均显示出较丰富的遗传多样性。遗传分化系数(Fst)表明,东极群体与烟台群体及乳山群体已明显分化,而烟台群体和乳山群体间无遗传分化,并且存在着较大的基因流。 相似文献
8.
鲈鱼群体生化遗传学研究Ⅱ.种群生化遗传结构及变异 总被引：3，自引：6，他引：3
1995年6月—1996年5月分别在汕头及青岛收集共100尾鲈鱼生化样品，采用淀粉胶及聚丙烯酰胺凝胶电泳分析了鲈鱼17种同工酶，记录出31个基因座位，统计了基因频率。结果表明，2群体间遗传相似度和遗传距离分别为0.9920和0.0080。作者初步认为中国近海鲈鱼为1个种，分南、北2个种群。汕头种群多态座位比例为22.6%，青岛种群为25.8%。x2检验表明，2个群体多态座位等位基因频率除汕头的Est-4外均符合Hardy-Weinberg平衡。汕头与青岛种群平均杂合度分别为0.079和0.099，表明目前鲈鱼种质资源状况尚好，但当前捕捞鲈鱼苗的压力过大，应严格控制鲈鱼苗的捕捞，以免因滥捕仔稚幼鱼而导致资源衰竭。 相似文献
9.
为探究不同地理条件下斑节对虾天然群体的遗传多样性和遗传分化水平, 选用14对简单重复序列(simple sequence repeat, SSR)特异引物对广东湛江、海南三亚、海南琼海的斑节对虾天然群体共计90尾个体进行微卫星标记分析, 每对引物检测出的等位基因数为2~4不等, 平均2.7。3个群体(湛江、三亚、琼海)平均有效等位基因分别为1.9081、1.9715和2.0185, 平均多态信息含量分别为0.3864、0.3926和0.4078, 总的平均期望杂合度(0.4605 )明显高于观测杂合度(0.4046), 表明3个群体遗传多样性水平为中等, 且存在杂合度缺失的现象。种群分化指数和遗传距离分析表明, 在不同群体间已产生了遗传分化, 但是分化较小; 三亚群体和琼海群体之间的亲缘关系最近, 而与湛江群体的亲缘关系最远。分子方差分析表明, 群体间的遗传变异指数为8%, 群体内个体间的遗传变异指数为92%, 基因分化主要发生在群体内, 而不是群体之间。 相似文献
10.
采用PCR技术,扩增了大连、乳山、烟台、舟山4个毛蚶(Scapharca subcrenata)地理群体共38个个体的线粒体COI基因部分序列,并分析了4个毛蚶群体的遗传多样性和系统发育关系。研究结果显示:38个毛蚶COI部分序列经处理得到长度均为625bp的基因片段,共分为30种单倍型;基于COI部分序列的分析结果,毛蚶4个地理群体总的变异位点为301个,多样性指数Pi为0.15048,平均核苷酸差异数为92.242,单倍型多样性指数S为241。聚类分析显示毛蚶大连群体、乳山群体和烟台群体具有高度的遗传多样性,3个群体交叉聚在一起,没有明显的群体分化;舟山群体单独聚为一支,与其他3个群体分化明显。研究表明,线粒体COI基因不能单独做为毛蚶大连、乳山和烟台群体的遗传标记,但可以作为毛蚶舟山群体的有效群体遗传标记,为线粒体COI基因在群体遗传学的应用提供了基础资料。 相似文献
11.
The genetic diversity and differentiation of four Zostera marina populations along the southern coast of Korea were estimated using random amplified polymorphic DNA (RAPD) markers to determine the effects of natural and anthropogenic stresses and reproductive strategy on within‐population genetic diversity. The mean number of alleles and gene diversities, indicating population genetic diversity, was highest in the Z. marina population that was exposed to repeated environmental disturbances, and lowest in the most undisturbed population. The higher genetic diversity in the disturbed population was associated with a higher contribution of sexual reproduction to population persistence. This suggests that both the level of disturbances and the reproductive strategy for population persistence contributed significantly to population genetic diversity at the study sites. According to the analysis of molecular variance (AMOVA), 76% genetic variation was attributable to differences among individuals within populations. The observed genetic differentiation (FST = 0.241) among Z. marina populations at the study sites appeared to result from reduced meadow size, increased genetic drift, and a high incidence of asexual reproduction. Increased population genetic diversity can enhance resistance and resilience to environmental disturbances; thus, this investigation of seagrass population genetics provides valuable new insights for the conservation, management, and restoration of seagrass habitats. 相似文献
12.
利用核糖体RNA的转录间隔区（ITS1）序列分析方法，以日本青蛤种群为外群，初步讨论了黄、渤海地区6个野生青蛤种群遗传变异和遗传结构。采用AMOVA方法对获得的24种单倍型序列进行了遗传变异水平和等级剖分。结果表明，ITS序列核酸多态性参数Pi为0．01973，Eta值为0．04624。青蛤各种群内的遗传变异水平较高，约占总变异的37．8％。但遗传变异的主要来源于不同组团（日本海与黄、渤海），其变异达到总量的61．36％。黄、渤海地区青蛤种群间的遗传距离在0．00311-0．14914之间，P检验没有出现显著差别，说明该地区青蛤种群没有出现遗传分化，并存在7种共享单倍型序列，种群间有一定的基因交流。日本种群与黄、渤海地区各种群的遗传距离在0．44803-0．54122之间，经P检验均出现了显著性差异，形成了明显的地理隔离及遗传分化格局。 相似文献
13.
AFLP analysis revealed differences in genetic diversity of four natural populations of Manila clam(Ruditapes philippinarum) in China 总被引：7，自引：0，他引：7
LIU Xiangquan BAO Zhenmin HU Jingjie WANG Shi ZHAN Aibin LIU Hui FANG Jianguang WANG Rucai 《海洋学报(英文版)》2007,26(1):150-158
1 IntroductionManila clam (Ruditapes philippinarum) is aworldwide distributed species. In China, it is foundfrom the northern to southern seashores (Wang etal., 1993; Zhuang, 2001). This species is eura-line with the salinity tolerance ranging from 20 to4… 相似文献
14.
采用线粒体Cytb基因测序技术研究了我国不同海域4个长蛸(Octopus variabilis)群体的种群遗传结构。结果表明,232bp的Cytb基因片段在4个群体90个个体中共检测到38个多态位点、12个单倍型,单倍型多样性指数H达0.854±0.015,核苷酸多样性指数Pi达0.059±0.005,平均核苷酸多样性指数K达13.526,显示出较高的遗传变异。种群遗传结构分析表明,4个群体间均存在极显著的遗传分化(P<0.01),除大连与青岛两群体间外,其它两两群体间的基因流均小于1。聚类分析表明,4个群体明显分化为三大类群,一个类群由大连和青岛群体组成,一个由温州群体组成,另一个由东山群体组成;遗传距离分析表明,东山类群与其它类群之间可能为亚种水平的分化,而其它类群之间仍为种内群体间分化。长蛸这种种群遗传结构形成原因可能与其较弱的种群扩散能力有关,另外冰川期地理历史因素及我国海域的洋流作用可能也参与了长蛸种群遗传结构的形成。 相似文献
15.
采用通用引物PCR扩增法,测定了辽东湾海域的白色霞水母(Cyanea nozakii)螅状体、碟状体及水母体的18S以及ITS-5.8S r DNA序列,同时利用Gene Bank数据库中已有同源序列对其进行序列分析及系统分析。结果显示,白色霞水母3个个体的18S和ITS-5.8S r DNA序列完全一致。白色霞水母样品的ITS-5.8S r DNA序列与Gen Bank中未知真核生物的序列高度相似(≥99%),推测该物种可能是早期发育阶段(卵、浮浪幼虫或碟状体)的白色霞水母样品。霞水母属不同种间18S r DNA序列经比对后同源序列长度为1709bp,多态位点数33个;比对后ITS1同源序列长度为368bp,其中变异位点203个,简约信息位点数178个,单变异位点21个。基于18S r DNA基因序列的霞水母属种内和种间平均遗传距离分别为0、0.008,而基于ITS1序列的霞水母属种内和种间平均遗传距离分别为0.019、0.284。基于ITS1的种间遗传距离是种内遗传距离的15倍,适合于进行物种鉴定。NJ系统树的结果也表明同种的不同个体各自聚枝,其聚类结果大致与形态分类吻合。研究表明,ITS基因片段在霞水母不同种间变异较大,更适于大型水母种类鉴定、检测及属内种间水平的系统进化研究。 相似文献
16.
采用高通量测序法从单环刺螠基因组中开发微卫星标记,并通过一个秦皇岛单环刺螠野生群体对其进行多态性评价,利用获得的多态性引物对秦皇岛、烟台、潍坊、青岛、大连5个不同海区的野生单环刺螠群体进行了遗传多样性及遗传结构分析。结果表明:本实验设计的50个微卫星标记能稳定扩增的有38个,其中22个微卫星位点在5个群体中均表现为高多态性,等位基因数(Na)介于24—44之间,多态信息含量(PIC)介于0.921—0.967之间。5个群体总的平均有效等位基因数(N_e)范围为6.629—8.850,平均观测杂合度(Ho)和平均期望杂合度(He)范围分别为0.790—0.912、0.851—0.896,大连群体的杂合度最大(H_e=0.8962),潍坊群体的最小(H_e=0.8510),其中有12个微卫星位点在不同群体中出现显著偏离Hardy-Weinberg平衡的现象。平均遗传分化指数(FST)表明,群体分化水平处于中等分化水平(FST值为0.0880—0.1136);聚类分析显示烟台群体先与青岛群体聚为一支,再与秦皇岛群体聚类,然后跟潍坊群体聚为一支,大连群体单独聚为一支;遗传距离模式(IBD)显示单环刺螠群体的地理距离与遗传距离间不存在显著的线性关系。本研究开发的22对微卫星标记可以用于单环刺螠遗传结构分析研究,为下一步单环刺螠种质资源保护和人工繁育提供参考依据。 相似文献
17.
采用ISSR分子标记对中国沿海4个厚壳贻贝群体进行遗传多样性和遗传结构分析,筛选出13条引物对4个群体120个样品共扩增出192个清晰的扩增位点,其中多态位点188个,多态位点百分率为97.92%,在物种水平上遗传多样性较为丰富。群体遗传多样性结果表明,PPL在81.77%—89.58%之间,H在0.2950—0.2818之间,I在0.4213—0.4447之间,其中福州群体多样性指数最低,温州群体最高。4个群体间GST为0.1519,Nm值范围介于3.0576—5.9714之间,AMOVA分析显示遗传变异主要来自群体内个体间。群体间遗传距离和聚类分析显示,温州群体和宁德群体首先聚为一支,再与舟山群体聚类,最后与福州群体聚在一起。表明地理位置较远的群体,遗传距离也较大,地理距离和遗传距离一致。 相似文献
18.
Population structure of Haliotis rubra from South Australia inferred from nuclear and mtDNA analyses 总被引：1，自引：0，他引：1
1Introduction ThemajorityofAustralia’sabalonefisheryex ports(5.135kt,worth＄216millionin2002～2003,ABARE2004)consistofblacklipabalone(HaliotisrubraLeach,1814).AssuchH.rubrais consideredasanimportantmarineresourcewithin Australia.Likemanyabalonespecieswor… 相似文献
19.
Genetic variation of 11 lines of Porphyra yezoensis from the coastline of Kagoshima ofJapan, Qingdao, Nantong, Putuo and Nanji Islands of China were studied by using amplified fragment length polymorphism (AFLP).778 bands were obtained with AFLP analysis of 16 primer combinations, among which 15 were unique, about 98.07% were polymorphic. The AFLP data showed that the closest genetic distance was 0.180 between two Kagoshima samples, and the farthest one was 0.397 between Kagoshima No.1 and Nantong No.9 line. The genetic distance showed that the variation was within the inner species scope. Neighbor-joining cluster and UPGMA cluster indicated that samples from Kagoshima and Qingdao were with high similarity and either with the samples of Nantong, Putuo and Nanji Islands. P. yezoensis in China shared high genetic diversity, and the genetic distance showed positive correlation with the geographic distance. 相似文献
20.
Molecular identification of ascaridoid nematodes from the deep-sea onion-eye grenadier (Macrourus berglax) from the East Greenland Sea 总被引：2，自引：0，他引：2
Esra Kellermanns Sven Klimpel Harry Wilhelm Palm 《Deep Sea Research Part I: Oceanographic Research Papers》2007,54(12):2194-2202
Macrourus berglax from the East Greenland Sea was studied for the presence of ascaridoid nematodes in 2001, 2002 and 2003. The fishes were collected between 278 and 413 m water depth using a benthopelagic net. Based on the amplification of the internal transcribed spacer ITS-1, 5.8S, ITS-2 and flanking sequences (=ITS+), three ascaridoid nematode species were identified. The prevalence of infestation during the 3 years ranged from 42.9% to 62.9% and 22.9% to 40.0% for the anisakids Anisakis simplex (s.s.) and Pseudoterranova decipiens (s.s.), respectively, and from 28.6% to 60.0% for the raphidascarid Hysterothylacium aduncum. A total of 18 specimens, two of each species and examination year, revealed no sibling species, suggesting a limited distribution of other ascaridoid siblings into the deep sea. The ITS-1, 5.8S and ITS-2 sequences of A. simplex (s.s.) from the East Greenland Sea did not differ from previously published sequence data (GenBank) from other regions in the Atlantic and Pacific oceans. The sequences of P. decipiens (s.s.) corresponded most closely to those of specimens from Richardson Bay, western Pacific, and differed in four positions (0.5%). They corresponded least to those of specimens from Japan (1.5%). The sequence data for H. aduncum differed in two positions in the ITS-1 (0.2%) and three positions in the ITS-2 (0.3%) from sequences from Japan. A high genetic similarity between the regions can be explained by (a) extensive final host migration in the case of A. simplex (s.s.), (b) an overlapping distribution of final host populations along the continental shelves for P. decipiens (s.s.) and (c) a low host specificity and large population size in the intermediate and final hosts for H. aduncum. The occurrence of the identified species in the macrourid fish underlines the potential of cosmopolitan ascaridoid nematodes to distribute not only horizontally but also vertically in the deep sea. 相似文献