Construction and analysis of a subtracted cDNA library of Betula platyphylla female inflorescence

Female inflorescence of Betula platyphylla was sampled at an interval of each two days to analyze the background of gene expression in floral phase. On the basis of SMART strategy, the driver cDNA was obtained from total RNA of the last sample and the tester cDNA was from that of the others by RT-PCR which were subsequently used to construct a subtracted cDNA library. The result of the ESTs (expression sequence tags) blastX showed that the genes in the subtracted cDNA library could be mainly clustered into 5 groups related to metabolism, transportation and signal transduction, cell cycle, stress response, and regulation. The relationship between gene expression and development was also discussed.     

休眠期珙桐种子cDNA文库构建及EST分析

以休眠期的珙桐种子为材料,利用SMARTTM cDNA Library Construction Kit构建珙桐种子的cDNA文库.结果表明:该文库的滴度为1.5×106 pfu·mL-1,重组率为98%,cDNA文库插入片段大小主要集中在0.5～1.0 kb.随机测序获得148个EST序列,拼接成127个uniEST,经网上BlastN及BlastX分析,其中75个序列是已知功能的基因标签,相似性较高,而32个序列在GenBank中相似性较低,13个序列在GenBank中没有匹配.这些数据有助于对珙桐种子的相关功能蛋白及分子机制的研究.     

白桦雌花序cDNA消减文库的构建及分析

为研究白桦雌花序花期基因表达情况,以两天为间隔对其进行取样.基于SMART策略,通过RT-PCR,将源自最后时期样品的cDNA作为Driver cDNA,源自其他时期样品的cDNA作为Tester cDNA,构建抑制性消减文库.EST序列经blastX分析表明,该文库中的基因大致可以归为五类,分别同代谢、物质运输和信号转导、细胞周期、胁迫反应及调控相关.本文对基因表达同发育的关系做了探讨.     

Analysis of expressed sequence tags in developing secondary xylem and shoot of <Emphasis Type="Italic">Acacia mangium</Emphasis>

Acacia mangium is a fast-growing tree widely planted in tropical countries because of its rapid growth, high wood density, high fiber quality, and good adaptability. Despite its importance as a fiber source in the pulp and paper industry, a large-scale analysis of expressed sequence tags (ESTs) has not been performed in A. mangium. In this study, we sequenced 10 752 clones of a normalized complementary DNA (cDNA) library prepared from A. mangium developing secondary xylem and shoot, and obtained a total of 8963 ESTs. The ESTs were assembled into 6220 unigenes comprising 1614 contigs and 4606 singletons. The unigene set was then subjected to various bioinformatic analyses. BlastN searches of the unigene set against the Gene Index Databases of soybean, Medicago truncatula, Lotus japonicus, grape, poplar, spruce, and pine demonstrated that the largest number of unigenes shared homologies with the soybean Gene Indices. BlastX searches against the TAIR9 peptide database enabled us to annotate the unigenes. Based on the annotation, we discussed whether the unigenes involved in the cell cycle, cell growth, shoot apical meristem development, and cell wall biosynthesis were present. This new genomic resource will accelerate the functional genomics of wood formation and molecular breeding to improve the wood properties of A. mangium.     

葡萄砧木研究概况

随着世界葡萄产业的发展,葡萄嫁接苗与嫁接栽培的应用越来越普遍,葡萄砧木品种的选育与研究也得到了重视.为更好地了解国内外葡萄砧木研究概况,该文对葡萄砧木选育情况,主要砧木品种的特性,及其对嫁接葡萄品种果实与所酿葡萄酒质量的影响等方面的研究情况进行了介绍.     

基于牡丹EST信息的滇牡丹SSR标记开发

对NCBI(美国国立生物技术信息中心)中牡丹的ESTs(expressed sequence tags)的序列进行分析,结果表明:在所分析的2 204条序列中,仅324条分布有SSRs(simple sequence repeats),占全部ESTs序列的14.70%;SSR的出现频率为15.20%,共计335个,其中,二核苷酸重复比例84.18%,三核苷酸重复比例为15.22%,四和六核苷酸重复比例为0.30%。在此基础上,利用软件(serafer 1.3)设计了51对备选SSR引物,以6个滇牡丹不同花色类群DNA为模板对引物进行筛选,其中,10对引物有扩增产物;用这些引物进一步在10个类群50个DNA模板进行多态性测试,结果显示:上述10对SSR引物均有多态性,且同一类群内不同模板DNA间也存在多态性。本研究结果证明:基于牡丹EST信息建立SSR标记是一种有效而可行的方法,有助于滇牡丹遗传多样性分析及基因组学方面的研究。     

松材线虫虫体特异表达cDNA文库的构建与分析

松材线虫取食和致病相关基因的鉴定是揭示松材线虫病致病机制的重要研究内容。以松材线虫混合虫体为测试方,线虫卵为驱动方,构建二者差减cDNA文库。文库测序结果经序列拼接、功能注释,共获得松材线虫虫体特异表达的有效EST序列354个,拼接后获得34个重叠群,其中15个重叠群获得明确的功能注释,其中MixC12、MixC25、MixC33分别与过氧化物酶、β-1,4内切葡聚糖酶、锌指家族蛋白有较高的同源性,这些基因被认为与植物线虫的取食和致病性密切相关。RT-PCR分析验证了所获得的差减cDNA的代表性。     

美洲黑杨雄性花芽cDNA克隆测序及表达序列标签(ESTs)特性分析

采用SMART技术构建美洲黑杨雄性花芽cDNA文库.随机挑选4 200个克隆进行序列测定,获得原始序列3 092个ESTs,去除插入片段短于150 bp的序列和污染序列后,获得有效ESTs序列3 087个,平均长度515 bp.对聚类后的416个Clusters分别进行单独拼接,得到相应的Contigs和Singletons分别为451和1 104个,并通过与NCBI等核酸数据库进行比对、查询和注释,获得已知功能和未知功能的基因1 015个,无序列相似性的新基因540个.这些数据为进一步研究高等植物花发育提供了一个极有价值的资源.     

Ectomycorrhizal communities associated with <Emphasis Type="Italic">Tilia amurensis</Emphasis> trees in natural versus urban forests of Heilongjiang in northeast China

The deciduous linden tree (Tilia amurensis Rupr.) is protected at National Level II in China as a species of ecological and economic importance. The objective of this study was to assess and compare the ectomycorrhizal communities associated with T. amurensis in natural versus urban forests of central Heilongjiang Province. The percentage of T. amurensis colonisation by ectomycorrhiza was more than 60 % in urban forests, compared to 34–49 % in natural forests. Use of a combination of morphological and molecular methods documented 18 ECM (ectomycorrhizal) types among three sites; 12–13 ECM species were identified in the natural sites versus 9 species in the urban site. Four ECM species (Boletus sp., Tuber sp., Inocybe sp.2, Leccinum sp.1) were the dominant mycorrhizal symbionts, and Cenococcum geophilum and Russula sp. were found only in the natural forests.     

美洲黑杨PdZFR基因的克隆和分析

根据美洲黑杨PdZFR部分cDNA序列,采用拟基因组文库步行法和RACE克隆了该基因全长cDNA及基因组DNA, 并对该基因的启动子、转录起始位点、内含子分布、剪切方式、编码的氨基酸序列和该基因在染色体上的分布位置进行了分析。组织或器官特异表达分析表明:该基因与植物发育相关。     

Ovicidal, larvicidal and anti-ovipositional activities of Bifora radians and other plant extracts on the grape berry moth Paralobesia viteana (Clemens)

Methanol extracts of Bifora radians, Arctium lappa, Humulus lupulus and Xanthium strumarium were tested against the North American grape berry moth, Paralobesia viteana in laboratory and greenhouse assays. Egg hatch was reduced by B. radians and X. strumarium extracts, whereas larval mortality was observed in response to B. radians, X. strumarium and A. lappa. Given the high mortality against egg and larval stages of this pest caused by extracts of B. radians, further studies were performed to determine the dose?Cresponse relationships between extracts of this plant and oviposition and egg hatch of P. viteana. There was a significant reduction in egglaying and egg hatch with increasing extract concentration, with 0.1% extracts providing 80% mortality and 1% extracts causing more than 90% control. This study demonstrates the potential of this plant extract for crop protection against a key pest of grapes and suggests that additional crop pests and field tests should be pursued to determine the efficacy of B. radians extracts as a biopesticide.     

Waxy bloom on grape berry surface is one important factor for oviposition of European grapevine moths

Grapevine moths are severe pest insects in European viticulture. Oviposition by grapevine moths is largely influenced by several physical and chemical cues located on the surface of their host plant’s fruits. The contribution of waxy bloom layer on the berry surface for oviposition decision of two European grapevine moth species, Eupoecilia ambiguella and Lobesia botrana, was investigated. An experimental setup was developed to prove oviposition preferences of both species for certain grape varieties and developmental stages based on epicuticular wax extracts. Chemical analysis of epicuticular wax patterns of four different Vitis vinifera varieties revealed differences. However, oleanolic acid was the main component on berry surface waxes and its relative amount decreased between early and late phenological stages. Furthermore, oleanolic acid was responsible for the preference of earlier phenological stages for E. ambiguella oviposition. However, ovipositional variety preferences were triggered by minor components on the wax berry layer. While the oviposition decision of L. botrana was mainly triggered by oleanolic acid, additional cues like olfactory and haptic ones were also important. The ovipositional preferences were discussed in accordance with the results of the chemical analysis in order to elucidate the role of wax compounds for oviposition stimulation.     

Cytotaxonomy and cytogeography ofVicia sect.Vicilla in Northeast of china

Vicia amirensis has pollen grain with swollen mesocipium, terete style, abaxially sprouting stylar hairs and globes stigma, differing from other five species,V. amoena, V. japonica, V. pseudo-orbus, V. ramuliflora, V. unijuga andV. venosa, in sect.Vicilla of Kupicha’s System. This result further support taxonomic treatmentV. amurensis proposed by Endo and Ohash. The chromosome numbers of 64 populations and karyotypes of 15 populations for sect.Vicilla and sect.Amurense were observed.V. amurensis andV. psendo-orbus have similar karyotype features such as the same karyotype symmetry, comparable chromosome size and the same type, of Sat-chromosomes, and thereforeV. amurensis in seet.Amurense is assumed to be closely related toV. japonica in sect.Vicilla. The primary study of nuclear DNA amount was carried out on nine populations of six taxa in sect.Vicilla in China. It is primarily discussed that evolutionary trend of karyotype, nuclear DNA amount in sect.Vicilla and geographic distribution of different ploidy cytotypes. (Responsible Editor: Zhu Hong)     

矿山型东南景天cDNA表达文库构建与耐镉基因筛选

以筛选出的镉超积累矿山型东南景天为材料,经镉胁迫后提取总RNA,纯化mRNA,利用改良SMART技术合成了全长cDNA,回收500 bp以上cDNA大片段克隆到改造过的大肠杆菌/酵母穿梭载体pYES2.0G中,建成东南景天镉全长cDNA文库,对随机挑取的阳性克隆进行PCR鉴定,插入片断大小在1 000 bp左右,说明所构建的文库达到了用于目的基因分离筛选和表达的建库要求,为将来筛选克隆与东南景天抗重金属相关基因奠定了基础。     

Characterization of expressed genes in the establishment of arbuscular mycorrhiza between Amorpha fruticosa and Glomus mosseae

Arbuscular mycorrhiza （AM） formed between plant roots and fungi is one of the most widespread symbiotic associations in nature. To understand the molecular mechanisms of AM formation, we profiled 30 symbiosis-related genes expressed in Amorpha fruticosa roots colonized by Glomus mosseae and in non-mycorrhizal roots at different stages using differential-display RT-PCR （DDRT-PCR）. The expressed genes were confirmed by reverse Northern blotting. Eleven fragments were sequenced and putatively identified by homologous alignment. Of the eleven AM-related genes, five were obtained at the early-stage of plant-fungus interaction and six at the later stage. Three expressed se-quence tag （ESTs） sequences were found to originate from the fungi and eight from the host plant by use of PCR evaluation of gDNA of both plant and fungi. The target genes included an ATP-binding cassette sub-family transporter gene, a transposon-insertion display band, and a photosynthesis-related gene. The results provided information on the molecular mechanisms underlying the development of mycorrhizal sym-biosis between woody plants and AM fungi.     

杉木木材形成过程扩展蛋白基因的克隆与表达分析

扩展蛋白是一类细胞壁结合蛋白,在一定的pH值下无需任何激活蛋白就可诱导细胞壁的伸展。以杉木木材形成的特异表达基因文库中获得的扩展蛋白ESTs序列为基础,通过RLM-RACE技术成功克隆到3条全长扩展蛋白基因。其中ClEXPA1 cDNA全长1033 bp,包括247个氨基酸的开放阅读框(ORF)区;ClEXPA2cDNA全长1374bp,包括268个氨基酸的开放阅读框;ClEXLA1cDNA全长1023bp,包括272个氨基酸的开放阅读框。进化树重建结果表明:ClEXPA1和ClEXPA2属于α-expansin(EXPA);ClEXLA1属于γ-expansin(EXLA)。实时定量PCR显示:ClEXPA1和ClEXPA2具有较为相同的表达模式,在形成层区域表达最高,在针叶及茎尖中度表达,成熟木质部表达较低,而根和花粉中几乎不表达;ClEXLA1在形成层及针叶中均有较高的表达,在木质部及茎尖中度表达,花粉中表达较低,而根中几乎检测不到。该组扩展蛋白的成功克隆,将为系统研究扩展蛋白在木材形成过程中的表达、功能及调控机制提供基因资源。