Genetic analysis and molecular mapping of a presenescing leaf gene psll in rice （Oryza sativa L.）

A rice psl1 （presenescing leaf） mutant was obtained from a japonica variety Zhonghua 11 via radiation of ^60Co-γ in M2 generation. Every leaf of the mutant began to wither after it reached the biggest length, while the leaves of the wild variety could keep green for 25--35 d. In this study, genetic analysis and gene mapping were carried out for the mutant identified. The SSR marker analysis showed that the mutant was controlled by a single recessive gene （psl1） located on chromosome 2. Fine mapping of the psl1 locus was conducted with 34 new STS markers developed around psl1 anchored region based on the sequence diversity between Nipponbare and 93-11. The psl1 was further mapped between two STS markers, STS2-19 and STS2-26, with genetic distances of 0.43 and 0.11 cM, respectively, while cosegregated with STS2-25. A BAC contig was found to span the psl1 locus, the region being delimited to 48 kb. This result was very useful for cloning of the psl1 gene.     

Genetic analysis and molecular mapping of a presenescing leaf gene psl1 in rice (Oryza sativa L.)

A rice psl1 (presenescing leaf) mutant was obtained from a japonica variety Zhonghua 11 via radiation of 60Co-γ in M2 generation. Every leaf of the mutant began to wither after it reached the big-gest length,while the leaves of the wild variety could keep green for 25―35 d. In this study,genetic analysis and gene mapping were carried out for the mutant identified. The SSR marker analysis showed that the mutant was controlled by a single recessive gene (psl1) located on chromosome 2. Fine mapping of the psl1 locus was conducted with 34 new STS markers developed around psl1 anchored region based on the sequence diversity between Nippon-bare and 93-11. The psl1 was further mapped be-tween two STS markers,STS2-19 and STS2-26,with genetic distances of 0.43 and 0.11 cM,respectively,while cosegregated with STS2-25. A BAC contig was found to span the psl1 locus,the region being delim-ited to 48 kb. This result was very useful for cloning of the psl1 gene.     

Fine mapping of a semidwarf gene sd-g in indica rice（Oryza sativa L.）

The semidwarf gene sd-g which has been usedin indiea rice breeding in southern China is a new one, non-allelic to sd-1. To map sd-g, an F2 population derived fromthe cross between Xinguiaishuangai and 02428 was con-structed. The sd-g was roughly mapped between two mi-crosatellite markers RM440 and RM163, with genetic dis-tances of 0.5 and 2.5 cM, respectively. Then nine new poly-morphic microsatellite markers were developed in this region.The sd-g was further mapped between two microsatellitemarkers SSR5-1 and SSR5-51, with genetic distances of 0.1and 0.3 cM, respectively, while cosegregated with SSR418. ABAC contig was found to span the sd-g locus, the region be-ing delimited to 85 kb. This result was very useful for cloningof the sd-g gene.     

盐藻(Dunaliella viridis)细菌人工染色体文库的构建和鉴定

盐藻具有极强的耐盐能力,是研究植物耐盐机制的模式系统.为了对其耐盐机制进行深入的 研究,以pCC1BAC为载体,构建了盐藻的细菌人工染色体（BAC）文库.该文库共有9 216 个转化子,插入片段平均长度为55 kb,以单克隆形式保藏在96块96孔板中,并建立了四维P CR基因筛选体系,可以通过4轮PCR快速筛选获得阳性单克隆.根据本实验室分离到的两个盐 藻基因的cDNA序列（ DvSPT2和DvTPSP ）设计引物,通过PCR从该文库中各筛到4个阳性BA C克 隆,说明该文库能有效用于分离盐藻基因的基因组序列,据此推测该文库约覆盖4倍盐藻基 因组序列.     

甘蓝型油菜Toc33基因启动子的克隆及序列分析

叶绿体是植物细胞中重要的细胞器,大部分叶绿体蛋白质都是由核基因组编码,在细胞质中合成分子量较大的前体蛋白,转运至叶绿体实施其功能．TOC33／TOC34是叶绿体上发现的一个外膜蛋白转运器构件蛋白,它与TOC159、TOC75和TOC64相互作用,构成了叶绿体外被膜上的一个蛋白转运器．目前已从豌豆（Pisumsa tizrurn）、拟南芥（Arabidopsis thaliana）、玉米（Zea mays）、小立碗藓（Physcomitrella patens）、诸葛菜（Orychophragmus violaceus）和油菜（Brassica napus）克隆到TOC33或TOC34的cDNA或DNA的编码区．与其功能研究相比,Toc33基因的表达调控研究较少,该基因5’端调控区域的克隆及序列分析均未见报道．为此,在本实验室已经克隆到甘蓝型油菜Toc33基因编码区的基础上,采用单引物PCR方法进行染色体步移,克隆出Toc33基因的启动子,为进一步研究Toc33基因的转录调控机制奠定基础．     

豇豆SSR标记在豌豆中的可转移性与应用初探

利用豇豆SSR引物筛选在豌豆具通用性的SSR引物。13对豇豆SSR引物中检测出8对引物在豌豆中可扩增,其中5对SSR引物表现出多态性,进而分析11个豌豆品种和5个豇豆品种的遗传多样性与遗传关系。结果表明:平均等位基因数、平均有效等位基因数、平均Shannon指数,在豌豆品种群中分别为2.00、1.64、0.55,豇豆品种群中分别为2.00、1.80、0.53,上述遗传参数反映出供试豌豆品种和豇豆品种具有中等水平的遗传多样性;利用UPGMA聚类分析,能将豌豆品种群和豇豆品种群分为两类,且每个品种群内的各个体之间能进行区分,尤其是两个豌豆品种亚群的聚类结果与其地理来源基本一致。     

微卫星标记在人参和西洋参鉴别中的应用

从GenBank中寻找含有简单重复序列(SSR)位点的人参DNA片段序列,设计SSR引物,挑选PCR扩增条带清晰的引物,对人参和西洋参进行PCR扩增及聚丙烯酰胺凝胶电泳分析,选择能够区别2个种的引物.共有来自8个SSR位点的9对引物能扩增出可区分人参和西洋参的特异性片段,其中7对SSR引物在西洋参中能稳定地扩增出特异性...     

Cupriavidus metallidurans CH34中2个苯酚降解基因簇的筛选与功能鉴定

Cupriavidus metallidurans(C.metallidurans)CH34是一种重金属耐受性细菌,能在以苯酚、甲苯酚、苯甲酸、苯胺等芳香族化合物为唯一碳源和能源的培养基中生长,其基因组中含有2个苯酚降解基因簇.以载体pIndigo-BAC 5构建C.metallidurans CH34的细菌人工染色体(bacterial artificial chromosome,BAC)文库,获得约3万个克隆,平均插入片段大小为30 kb,插入频率为98%,推测该文库覆盖CH34基因组约1 240倍.用PCR筛选文库中的3 000个单克隆,共获得9个阳性克隆,其中5个克隆含有长基因簇,4个含有短基因簇,并从中得到含有全长苯酚降解基因簇的克隆.利用以苯酚为唯一碳源的无机盐培养基,研究2个基因簇在大肠杆菌中的表达情况.结果显示,两个基因簇均表现出了苯酚降解能力,短簇的降酚能力要优于长簇.     

Verification and fine-mapping of QTLs conferring days to flowering in soybean using residual heterozygous lines

The results of QTL mapping based on a primary mapping population should be further verified and refined for its real utilization in marker-assisted selection or map-based cloning.The primary mapping population contains 114 BC1F1 plants of the backcross between Essex (maturity group V,MG V) as the donor parent and ZDD2315 (MG II) as the recurrent parent.In this study,a genetic linkage map with 250 SSR markers spanning a total length of 2963.5 cM on 25 linkage groups (LG) was constructed using software MAPMAK...     

Studies of new EST-SSRs derived from Gossypium barbadense

Existing cotton EST-SSR markers are mostly derived from Gossypium arboreum and Gossypium hir-sutum, but EST-SSR markers from Gossypium barbadense are scarce. One hundred and nineteen EST-SSRs were developed based on 98 unique ESTs from a cDNA library constructed in our laboratory using developing fibers from G. barbadense cv. Pima3-79. Among the SSRs, trinucleotide AAG appeared at a high frequency of 11.76%. 36 accessions (consisting of 13 diploids of the A genome, 11 diploids of the D genome and 12 allotetraploids of the AD genome) were employed to test new EST-SSRs. 76 EST-SSRs were successfully amplified, and 313 polymorphic fragments were yielded, with an average of 4.11 fragments per primer pair. The PIC ranged from 0.17 to 0.95 with an average of 0.53. Based on Jaccard’s genetic similarity coefficient, these 36 accessions were clustered into three groups. 21 EST-SSRs exhibited polymorphisms in BC1 population ((Emian22 × Pima3-79) × Emian22), 24 polymor- phic loci were generated, while 22 of the 24 polymorphic loci were integrated with our interspecific BC1 backbone genetic linkage map, and anchored in 12 chromosomes. This study effectively proved that EST-SSRs from G. barbadense are valuable for genetic diversity analysis and genetic mapping.     

基于SSR标记的丛生竹杂种鉴定、遗传分析和指纹图谱构建

[目的]准确鉴定丛生竹杂交种,分析杂种及其亲本的遗传关系,开发可以利用的指纹图谱.[方法]以孝顺竹(Bambusa multiplex)×麻竹(Dendrocalamus latiflorus)、孝顺竹(B.multiplex)×粉单竹(B.chungii)两个杂交群体为材料,从已公布的竹子SSR引物中随机选取30对引...     

Cupriavidus necator JMP134细菌人工染色体基因组文库的构建与鉴定

Cupriavidus necator JMP134(C.necator JMP134)可以降解60多种芳香族化合物,在环境污染治理方面具有良好的应用前景.该菌株基因组含有两个苯酚降解基因簇,克隆并研究其功能具有重要的理论和应用价值.以pIndigo-BAC 5为载体,构建了C.necator JMP134的细菌人工染...     

甜菊钙调蛋白基因的克隆及结构分析

钙调蛋白（Calmodulin）是生物细胞内一种重要的调控蛋白，通过其与靶酶的相互作用控制细胞正常的生长发育及细胞对外界环境变化的反应，我们从甜菊顶芽和花芽中提取总RNA，逆转录合成cDNA第一链，以此为模板，参考GenBank上已发表植物的钙调蛋白基因序列合成5′端和3′端引物，利用多聚酶链式反应（PCR）扩增并克隆得到了甜菊钙调蛋白基因的两个异型基因，序列分析表明，它们均由450个核苷酸组成，编码148个氨基酸，在核苷酸序列上与迄今已知的多种植物钙调蛋白均有很高的同源性，同源率在83％以上，编码的氨基酸序列同源性更同，同源率高达95％以上，这两个基因之间存在差异，其核苷酸序列同源率为85％，编码区的氨基酸序列的同源率为99％，仅在第122个氨基酸由ALA代替了VAL。     

Sequence analysis of the gene correlated with cytoplasmic male sterility (CMS) in rape-seed (Brassica napus) Polima and Shaan 2A

orf224 is a CMS-related mitochondrial gene discovered in Polima cytoplasm. Shaan 2A CMS line is the parent of the first rapeseed hybrid cultivar Qinyou No. 2that has been grown in many regions of China. In this work,genomic DNA of Polima CMS line and Shaan 2A CMS line were used as templates, two primers of specific oligonucleoamplification fragments were cloned into pGEM-T Easy vectors and DNA sequences were determined. The CMSassociated gene, orf224-1 present in Shaan 2A CMS line, has a sequence highly homologous to the orf224 of the Polima CMS line, except for one nucleotide at position +398. There were only one base (AAC→AGC) and one amino acid (Asn →Ser) differences between the two. The homologies of the two sequences in nucleotide and. amino acid were 99.9 % and 99.6%, respectively. It is concluded that orf224 in Polima CMS line and orf224-1 of Shaan 2A CMS line are the allele at the same locus in mitochondria.``