中国龙虾微卫星标记的筛选及遗传多样性分析

文章以M13通用引物和重复序列(CT)₁₅、(AT)₁₅引物, 利用PCR法对中国龙虾(Panulirus stimpsoni Hoehuis)部分基因组DNA文库进行筛选。共获得78个微卫星序列, 分别分布于55个阳性重组克隆中, 其中完美型(perfect)共50个, 占64%; 非完美型(imperfect)3个, 占3.8%; 混合完美型(compound perfect)6个, 占7.7%; 混合非完美型(compound imperfect)19个, 占24.5%。根据微卫星序列, 设计并筛选出15对微卫星多态性引物, 对中国龙虾的群体进行了遗传多样性分析。获得3~12个等位基因, 等位基因大小在78~425 bp之间, 基本符合引物设计的理论长度。期望杂合度范围为0.48~0.87, 平均值为0.71, 表明中国龙虾基因组微卫星具有较高的杂合度与遗传多样性。15个微卫星位点的PIC值从0.44到0.84, 平均值为0.60, 说明这些微卫星位点在中国龙虾基因组中包含丰富的遗传信息, 合适用于中国龙虾的各种分子标记及遗传学分析和应用。     

巴氏蘑菇微卫星序列的分离及其对Co60辐射诱变菌株的鉴别

根据链霉素磁珠和生物素特异结合的特性,用生物素标记的二聚核苷酸重复序列探针从巴氏蘑菇的基因组中分离微卫星序列。将结合于链霉素磁珠上的标记探针同两端连接已知序列人工接头的巴氏蘑菇DNA酶切片段杂交。洗脱未杂交DNA片段后,用磁珠富集的片段建立微卫星文库。挑取522个菌落用对应重复序列为引物进行PCR筛选,得到48个阳性克隆,经测序有32个菌落含微卫星序列。微卫星富集效率为阳性克隆数的67%,总克隆数的6%。除去重复或无效的微卫星序列,在设计出的12对用于鉴别85个巴氏蘑菇的Co60辐射变异株微卫星引物中,有4对引物总共扩增出明显的变异菌株17个。证明有些微卫星位点可用于巴氏蘑菇辐射变异品种的指纹筛选与鉴别。     

中缅树鼩微卫星分子标记的筛选

目的 筛选中缅树鼩微卫星分子标记,逐步填补中缅树鼩特异性遗传标记的空白.方法 建立中缅树鼩基因小片段插入文库,利用5’端地高辛标记的(CA)15探针从约1500个菌落中选出36个阳性克隆.对这些克隆进行测序,发现其中15个含有重复序列,其中1个为重复克隆,1个因两端序列太短而不能设计引物.结果 用Primer3软件设计...     

东方田鼠部分BAC文库的微卫星筛选

目的 从东方田鼠的部分BAC文库中筛选微卫星.方法 应用非放射性的菌落杂交方法和磁珠富集法从东方田鼠的BAC文库中筛选高质量的微卫星标记.结果 以地高辛标记的寡聚核苷酸(CA)20为探针,通过菌落杂交法从136个东方田鼠BAC克隆中筛选出杂交信号最强的20个阳性克隆.再将这20个阳性克隆分别通过链霉亲和素磁珠法构建亚克隆文库,从中选取400个经PCR鉴定为阳性的亚克隆进一步测序分析,共得到220个微卫星序列,阳性率55％.选取重复次数高,侧翼序列完整的微卫星序列设计74对引物,共有35对引物能扩增出清晰的条带,其中16对引物具有多态性.结论 成功且高效地从阳性BAC克隆中筛选出微卫星序列,这些微卫星和阳性BAC克隆可用于后续的定位研究.     

Dynal磁珠富集大熊猫微卫星标记

应用Dynal磁珠-生物素标记的微卫星探针与大熊猫基因组酶切片段杂交,捕获400—600bp含有微卫星序列的DNA片段,连接到pGEM-T载体中,构建富集微卫星序列的小片段插入文库。应用γ^32P标记的探针筛选文库,从2880个转化子中获得了260个阳性克隆。对54个序列进行了测序,并成功地设计了大熊猫微卫星引物37对。该方法能有效提高筛选微卫星标记的效率。     

伊犁鲈微卫星位点的筛选及近缘物种通用性

为开发伊犁鲈(Perca schrenkii)分子标记用于鲈属鱼类种质资源保护,以伊犁鲈为材料,应用磁珠富集法进行了微卫星标记的筛选.从伊犁鲈尾鳍提取总DNA,进行酶切、接头连接、PCR扩增,再采用生物素标记(CA)15探针及生物素标记(TG)15探针对扩增产物进行杂交富集,经再次PCR扩增及T-A克隆,成功构建了伊犁鲈基因组微卫星富集文库.采用重复序列引物筛选获得阳性克隆,随机选取48个阳性克隆进行测序,测得序列46个,其中38个克隆含有微卫星序列,41个位点的微卫星重复数在8次以上.根据测得序列设计17对微卫星引物,均能在伊犁鲈群体中扩增获得目的条带.采用该17对引物对河鲈(P.fluviatilis)及黄金鲈(P.flavescens)群体样本进行扩增,10对引物具有通用性,其中6对在河鲈中具有高度多态性(PIC>0.5),5对在黄金鲈中具有高度多态性.     

豚鼠基因组26个多态性微卫星标记的筛选

目的筛选豚鼠基因组的多态性微卫星标记,为豚鼠遗传质量控制及基因定位等工作奠定基础。方法采用磁珠富集法和豚鼠基因组数据库筛选法获取微卫星位点序列,通过分析和初步筛选,挑选部分候选位点,根据其序列设计引物,对5种不同来源的豚鼠基因组DNA标本进行PCR扩增,以期获得多态性分子标记。结果本实验采用磁珠富集法共获得微卫星序列304个,设计引物125对,最终获得多态性位点1个,暂未发现多态性的特异性位点17个;用数据库筛选法共获得微卫星序列292个,设计并合成相应引物178对,最终发现多态性位点25个,暂未发现多态性的特异性位点28个。结论本实验获得26个多态性微卫星标记,45个潜在的候选标记,为微卫星标记在豚鼠遗传质量监测及突变基因定位等工作的应用奠定了基础。     

丁坝对鱼类栖地的影响范围评估

利用磁珠富集法和5’锚定PCR法开发背瘤丽蚌的微卫星标记,将获得的多态性引物用于群体的遗传多态性分析,以期在比较两种开发微卫星标记方法的基础上同时获得一批有用的微卫星引物。从磁珠富集法获得的微卫星序列阳性克隆率为69.2%,重复次数超过10的占总数的70.2%,从设计的28对引物中筛选得到多态性引物11对,开发效率为39.3%。这11对引物用于养殖群体的遗传多样性分析,结果显示,等位基因数范围为4～13,观测杂合度、期望杂合度范围分别为0.205～0.738、0.566～0.839。而5’锚定PCR法获得的微卫星序列阳性克隆率为97.8%,重复次数超过10的占总数的24.7%,从设计的56对引物中筛选得到多态性引物19对,开发效率为30.4%。这19对引物用于养殖群体的遗传多样性分析,结果显示,等位基因数范围为3～10,观测杂合度、期望杂合度范围分别为0.208～0.894、0.431～0.896。实验结果表明,磁珠富集法所获微卫星序列质量高,开发微卫星标记效率较高;而5’锚定PCR法实验操作更简便,所获得的引物遗传多样性指数更高。两种方法开发的引物均可用于背瘤丽蚌和近缘种的野生种质资源遗传多样性研究。     

细梢小卷蛾微卫星富集文库的构建与分析

目的:构建细梢小卷蛾Rhyacionia leptotubula微卫星富集文库.方法:提取细梢小卷蛾基因组DNA,经限制性内切酶Rsa Ⅰ酶切,用(CT)10和(GT)10生物素探针与其杂交,利用磁珠富集含有微卫星的DNA序列,并对其进行PCR扩增,将扩增产物连接到pMD18-T载体后转入感受态大肠杆菌DH5α中,得到微卫星富集文库:结果:对100个克隆进行随机测序,获得98个微卫星序列,其中具有5次及以上碱基重复次数的微卫星克隆占26%,最高碱基重复次数为33次,非完美型占12%,说明构建的细梢小卷蛾微卫星富集文库是一个高质量的文库.结论:该文库的建立为后续筛选具高多态性的微卫星标记引物研究细梢小卷蛾的种群遗传结构、迁移扩散规律等奠定了基础.     

岩原鲤微卫星富集文库的构建及微卫星分子标记的筛选

用磁珠富集法构建了岩原鲤Procypris rabaudi AC重复和GATA重复的微卫星富集文库.采用PCR方法分别以人工合成的oligoA和探针(AC)12或(GATA)6为引物筛选含有微卫星的阳性克隆.(AC)n 富集库和(GATA)n富集库的阳性克隆率分别为30%和7%左右.对40个AC重复的阳性克隆和30个GATA重复的阳性克隆测序,共获得61个微卫星序列,其中包含了一个三碱基重复(TGA)的微卫星序列.选择设计了19对AC重复和16对GATA重复的微卫星引物以及1对TGA重复的微卫星引物,通过PCR优化,共有20对引物能够产生稳定、清晰的目的产物带.为了检测获得的岩原鲤微卫星座位是否能用于近缘物种的研究,我们将20对岩原鲤微卫星引物用于中华倒刺鲃Spinibarbus sinensis基因组DNA PCR扩增,有60%的引物对能产生特异性的目的条带.本研究获得的20个岩原鲤微卫星座位可以用于岩原鲤及近缘物种的遗传多样性、种群遗传结构等的进一步研究.     

华北地区六种熊蜂的地理分布及生态习性

2005～2007年连续3年对华北地区小峰熊蜂Bombus hypocrita、密林熊蜂B.patagiatus、红光熊蜂B.ignitus、明亮熊蜂B.lucorum、火红熊蜂B.pyrosoma和重黄熊蜂B.picipes等6种熊蜂的地理分布和生态习性进行研究。结果表明,这6种熊蜂在华北地区的地理分布差异很大,火红熊蜂分布最广,重黄熊蜂分布最窄。6种熊蜂在垂直分布上也存在差异,红光熊蜂分布于较低海拔高度地区,明亮熊蜂分布于较高海拔高度地区,但在海拔1300～1800m范围内6种熊蜂都有分布。6种熊蜂中,火红熊蜂的年活动周期较长,为180天左右。小峰熊蜂、明亮熊蜂、密林熊蜂和重黄熊蜂的年活动周期居中。红光熊蜂的年活动周期最短,为140天左右。6种熊蜂采访植物涉及到17科63种,采访植物存在一定的偏好性,主要采访豆科、菊科、蔷薇科和唇形科等植物;而且,不同种熊蜂采集植物的种类也存在较大差异。     

Polymorphic microsatellites in the Reeves's pheasant developed by cross-species amplification

Cross-species microsatellite amplification is an effective way of obtaining microsatellite loci for closely related taxa in bird species. The Reeves's pheasant, Syrmaticus reevesii, is a vulnerable species endemic to China. To improve population genetics and parentage analysis studies in this species, we obtained nine polymorphic microsatellite markers, in addition to the nine markers previously isolated, from the cross-species amplification of 52 markers. The number of alleles per locus varied between two and 12 with expected heterozygosity ranging from 0.298 to 0.714 (n = 107). The success rates of simulated paternity tests using CERVUS software improved at different confidence levels after adding these markers to the previous ones.     

Isolation and characterization of microsatellite markers in the striped hamster (Cricetulus barabensis)

A total of 14 polymorphic microsatellite markers were isolated and characterized from the striped hamster, Cricetulus barabensis, a widespread rodent pest in northern China. Two to six alleles per locus were detected in 90 individuals from three locations in Shandong Province, China. The observed and expected heterozygosities ranged from 0.21 to 0.78 and from 0.30 to 0.80, respectively. These microsatellite markers provide new tools for investigating the population structure of this species.     

Characterization of microsatellite loci in fulvous fruit bat Rousettus leschenaulti

Rousettus leschenaulti is an abundant species in many countries of South‐East Asia, including south China. We isolated seven microsatellite loci in R. leschenaulti from genomic DNA enriched for CA repeats with the enriched library method. A total of 56 samples from a population in the Guangxi Province of China were tested with these microsatellite markers. The polymorphism ranged from seven to 16 alleles, and the observed heterozygosity was 84–94%. It is the first time microsatellite markers were characterized from R. leschenaulti, and these markers can be an important tool for analysing population structure and genotypic diversity.     

Development and characterization of 60 microsatellite markers in the abalone Haliotis diversicolor

The abalone, Haliotis diversicolor, is one of the most important mariculture species in southern China. We developed 60 new polymorphic microsatellite markers for H. diversicolor and characterized them in 30 individuals from a cultured population in Sanya, China. All 60 markers were found to be polymorphic. The number of alleles ranged from two to nine per locus, with an average of 4.12/locus. The expected and observed heterozygosities ranged from 0.10 to 0.88 and from 0.07 to 0.87, respectively. Forty-four loci were in Hardy-Weinberg equilibrium. These 44 microsatellite markers should be useful for genome mapping and population genetic studies.     

Development of microsatellite markers from Cercis chinensis (Fabaceae)

? Premise of the study: Microsatellite markers were developed to characterize the level of genetic diversity and population genetic structure of Cercis chinensis, a widely cultivated garden plant in China with congeneric species disjunctly distributed in East Asia, North America, and the Mediterranean. ? Methods and Results: Using the Fast Isolation by AFLP of Sequences COntaining repeats (FIASCO) protocol, eight microsatellite markers were developed in C. chinensis. Seven of the markers displayed polymorphism, with the number of alleles ranging from one to four in four populations of C. chinensis. Four to six microsatellite loci exhibited interspecific transferability in C. glabra, C. chuniana, and C. chingii. ? Conclusions: These are the first microsatellite markers developed for C. chinensis, which will be further used in investigation of population genetic structure and phylogeographic pattern of C. chinensis and its congeneric species.     

Development and characterization of microsatellite markers in Eucommia ulmoides Oliver (Eucommiaceae)

Twenty‐three microsatellite markers were developed from an AC‐enriched genomic library of Eucommia ulmoides, an economically important tree species for both herbal medicine and organic chemical industry in China. Nineteen microsatellite loci were found polymorphic by testing 36 individuals from 10 populations, with two to 14 alleles per locus. The expected heterozygosity ranged from 0.054 to 0.874. This set of microsatellite markers has provided a useful tool for the ongoing efforts in studying population genetic structure of E. ulmoides.     

Development and characterization of microsatellite markers for <Emphasis Type="Italic">Camellia nitidissima</Emphasis>

Camellia nitidissima Chi (Theaceae), a rare and famous plant with golden-yellow flowers, narrowly distributes in Southwest China and North Vienam. It is now endangered and its distribution is ongoing shrinked due to deforestation and collection of seeds for horticulture. From repetitive DNA enriched libraries, we reported here the development and characterization of ten microsatellite markers for this species. The number of alleles ranged from 5 to 12. Observed and expected heterozygosities ranged from 0.4583 to 0.9474, and 0.6976 to 0.9033, respectively. These ten polymorphic microsatellite loci is the first set of microsatellite markers for C. nitidissima, and they will be used for future study of conservation genetics of this species.     

A genetic linkage map of Pacific white shrimp (<Emphasis Type="Italic">Litopenaeus vannamei</Emphasis>): sex-linked microsatellite markers and high recombination rates

Pacific white shrimp (Litopenaeus vannamei) is the leading species farmed in the Western Hemisphere and an economically important aquaculture species in China. In this project, a genetic linkage map was constructed using amplified fragment length polymorphism (AFLP) and microsatellite markers. One hundred and eight select AFLP primer combinations and 30 polymorphic microsatellite markers produced 2071 markers that were polymorphic in either of the parents and segregated in the progeny. Of these segregating markers, 319 were mapped to 45 linkage groups of the female framework map, covering a total of 4134.4 cM; and 267 markers were assigned to 45 linkage groups of the male map, covering a total of 3220.9 cM. High recombination rates were found in both parental maps. A sex-linked microsatellite marker was mapped on the female map with 6.6 cM to sex and a LOD of 17.8, two other microsatellite markers were also linked with both 8.6 cM to sex and LOD score of 14.3 and 16.4. The genetic maps presented here will serve as a basis for the construction of a high-resolution genetic map, quantitative trait loci (QTLs) detection, marker-assisted selection (MAS) and comparative genome mapping.     

Isolation and characterization of nine polymorphic microsatellite markers of the marbled rockfish Sebastiscus marmoratus (Scorpaeniformes, Scorpaenidae)

Sebastiscus marmoratus is a typical sedentary fish and usually lives at the bottom of the coastal zone from Japan to the East China Sea. Next-generation sequencing platform was used to obtain microsatellite loci sequences of S. marmoratus, among which forty-eight perfect microsatellite repeats were suitable for primer design. Nine polymorphic microsatellite markers were exploited and characterized for it. The allele number of all polymorphic microsatellite markers ranged from 4 to 12. Expected and observed heterozygosity varied from 0.302 to 0.909 and from 0.190 to 0.625, respectively. In further studies, the genetic variation and population structure of this species would be investigated using these microsatellite loci.