绵羊regakine-1基因的克隆与序列分析

【研究目的】克隆并分析绵羊regakine-1基因;【方法】肠系膜淋巴结组织提取总RNA,利用设计的引物进行RT-PCR,PCR产物与pMD-19T载体连接后转化JM109感受态细胞,筛选阳性克隆、测序,并进行序列分析;【结果】克隆的绵羊regakine-1基因与牛的同源性为91%,推测的氨基酸序列信号肽为1￣21aa,SCY结构域为29￣87aa,结构特征与牛的相一致。【结论】克隆了绵羊regakine-1基因的ORF,并注册GenBank(AccessionEF617337)。     

H9N2亚型禽流感安徽分离株CK/AH/1/10的分子特征

为了了解H9N2亚型禽流感病毒安徽分离株CK/AH/1/10基因组的分子特征,本研究采用RT-PCR方法扩增了CK/AH/1/10分离株8个片段的基因,克隆测序后进行同源性比较及遗传进化分析。结果显示:分离株CK/AH/1/10 HA蛋白的裂解位点为低致病性禽流感病毒,参照Guan等[4]对H9亚型禽流感病毒HA基因的分类标准,可将CK/AH/1/10株归属于欧亚系G9-like亚分支。     

利用聚合酶链式反应技术研究单粒古代稻谷(公元800年)离体DNA片段的扩增

在东南亚地区已发掘出很多古代稻谷,如果能从这些古稻谷中把DNA提出加以分析,可以得到有关栽培稻的系统分化和地理传播方面的直接信息。古代稻种的基因型相当复杂,必须要能从单粒种子开始分析,方能得到有价值的资料。为此,我们进行了从单粒古稻谷中提取DNA的研究工作。本研究采用通常提取植物组织中DNA的方法。从在日本挖掘出的古代稻谷单粒种子中提取出了50—100ng左右的DNA片段。以这些DNA作为模板,用聚合酶链式反应(Polymerase Chain Reaction,PCR)技术将DNA加以扩增。由其中几个DNA片段初步合成了相当于水稻光敏色素基因的DNA序列。     

Development of a Pathotype Specific SCAR Marker in Plasmodiophora brassicae

Plasmodiophora brassicae is an obligate biotroph that causes clubroot, one of the most damaging diseases of crucifers. Breeding of clubroot-resistant plants has been hampered by the large variation of pathogenicity in P. brassicae and by the lack of an efficient means for detecting specific isolates. To improve the practicality of P. brassicae pathotype-identification, a molecular approach was developed. RAPD profiles of 37 single-spore-derived isolates belonging to seven different pathotypes were compared. A RAPD marker, OPL14₁₂₀₀, was found in the molecular pattern of all the isolates belonging to one particular pathotype (P1), pathogenic on all differential hosts tested. The DNA band corresponding to this marker was cloned and sequenced. No significant homology to previously characterised nucleotide sequences was found. Primers were designed to specifically amplify the OPL14₁₂₀₀ band. The SCAR marker was observed in all isolates belonging to pathotype P1 and was absent in isolates belonging to other pathotypes and in the different plant hosts analysed. The SCAR marker was also generated from direct amplification of DNA from clubs (mixture of host and pathogen DNA) developed after infection by P1 isolates. This molecular marker may be a valuable tool for rapid and reliable identification of P. brassicae P1 isolates in areas where resistant varieties are cultivated.     

黄麻应用核心种质的DNA分子身份证构建

构建并研究黄麻应用核心种质是促进黄麻遗传育种和挖掘优异基因的必要途径。在300份黄麻种质资源的农艺性状观察统计基础上,构建了黄麻应用核心种质,包含61份品种(系),可划分为高产、优质、抗病等16种应用类型。为准确鉴定这61份应用核心种质,以46对核心引物为基础,筛选出12对荧光核心引物,采用荧光标记毛细管电泳分析这12对引物的多态性,共检测出140个多态性位点。将毛细管电泳得到的分子量数据以数字+英文字母方式编码,选取了12对荧光核心引物的组合,构建出该应用核心种质的字符串DNA分子身份证,进而构建了相应的条形码和二维码DNA分子身份证,可迅速被电子设备识别。这些结果可促进黄麻种质资源的高效利用及快速分子鉴定。     

67份美国小麦品种矮秆基因的分子标记检测

为了明确矮秆基因在美国小麦品种中的分布特点并发掘较少利用的矮秆基因,本研究利用8个小麦矮秆基因的特异分子标记对67份美国小麦品种中的矮秆基因进行了检测。结果表明,67份美国小麦品种中,超过80%的品种（56个）含有矮秆基因,其中 Rht-B1b和 Rht8基因频率较高,分别占62.7%和43.3%。仅有5个品种含有 Rht-D1b基因,同时发现3个品种含有 Rht5基因,2个品种含有 Rht12基因,未发现含有 Rht4、 Rht9和 Rht13基因的品种。在含有矮秆基因的品种中,35.8%的品种含有2个或2个以上的矮秆基因。其中有1个品种同时含有3个矮秆基因,有20个品种同时含有 Rht-B1b和 Rht8基因,有3个品种同时含有 Rht-D1b和 Rht8基因,有1个品种同时含有 Rht-D1b和 Rht12基因,其余32个品种各含有1个矮秆基因。本研究未发现同时含有 Rht-B1b、 Rht-D1b、 Rht8以及同时含有 Rht-B1b、 Rht-D1b的品种。     

植物内质网小分子量热激蛋白的生物学功能

介绍了植物ERs HSP的结构特点、分子伴侣活性及逆境抗性等生物学功能,并展望了该领域今后的研究方向,为深入研究植物的逆境胁迫机制以及分子水平的作物育种提供了新思路。     

基于ISSR分子标记的海南凤仙花种群遗传多样性

运用ISSR分子标记技术,分析海南岛石灰岩地区海南凤仙花自然种群的遗传结构,比较3个海拔梯度对种群遗传结构的影响。结果显示,13个ISSR引物的扩增结果显示其多态性位点百分率为97.7%。AMOVA分析表明:海南凤仙花自然种群的变异主要来自种群内(92%),而种群间变异较少(8%);中海拔种群的遗传多样性最为丰富;而高海拔种群的遗传多样性则较低;种群的遗传距离和地理距离表现出显著的高度相关性。说明海拔是影响种群基因流的重要因素,高海拔种群可以向中低海拔种群进行传播花粉和种子等基因流动,而中低海拔种群向高海拔种群进行类似的基因流动则较为困难,海南凤仙花数量较少的主要原因可能来自于其生境的限制。因此在以后的保护工作中要特别注重其生境的保护,避免人为因素的破坏。     

Genetic differentiation among Ecuadorian Theobroma cacao L. accessions using DNA and morphological analyses

The quality of Ecuadorian cacao is presently threatened by the introduction of hybrid material. An estimation of genetic diversity in Ecuador is required in order to avoid the loss of fine flavored cocoa. Genetic variability amongst 60 Ecuadorian genotypes of Theobroma cacao has been evaluated using molecular and phenotypic markers. The two distance matrices derived from the molecular and phenotypic data were found to be correlated (R² = 0.5). Dynamic clustering analyses classified the genotypes in two or three groups depending on the markers used. The genotypes coming from Sebasti{àn Arteaga (SA) and Balao Chico (BCH) plantations appeared related to each other suggesting a common genetic origin. They also may be considered as a distinct group with high RFLP homozygosity. The EETP (Estací}on Experimental Tropical Pichilingue of Ecuador) collection was comprised of more variable genotypes possessing variable heterozygosity levels. The low heterozygous genotypes may be genetically related to SA and BCH trees, whereas the higher heterozygous genotypes may have resulted from hybridizations between original Nacional material of Ecuador and genotypes imported from Trinidad at the beginning of the century. Thus genetic introgression may have occurred giving rise to a range of variation between Nacional and hybrid forms. This revised version was published online in July 2006 with corrections to the Cover Date.     

高频率诱导马铃薯双单倍体的研究

通过４ｘ—２ｘ杂交测验，从Ｓｏｌａｎｕｍｐｈｕｒｅｊａ后代中筛选出９份诱导双单倍体频率和花粉育性高的授粉者．它们的平均诱导率为３３株双单倍体／１００个果，并具有显性纯合的胚斑标记基因（ＢＢ）和紫色胚轴标记基因（ＰＰ），可用来有效地识别双单倍体．不同的四倍体母本产生双单倍体的频率不同，中薯２号产生频率最高，达３４株双单倍体／１００个果，母本基因型对双单倍体的产生有很大的影响．