盾叶薯蓣3-羟基,3-甲基戊二单酰辅酶A还原酶和环阿屯醇合成酶基因克隆及序列分析

根据已报道的植物3-羟基,3-甲基戊二单酰辅酶A还原酶(HMGR)和环阿屯醇合成酶(CS)基因保守序列分别合成简并引物,先后从盾叶薯蓣(Dioscorea zingiberensis)幼苗中克隆了一段663 bp(HMGR-DZh)和一段1 245 bp(CS-DZc)的cDNA片段,经NCBI和CLUSTALW在线序列同源分析,结果表明,由HMGR-DZhcDNA推导的蛋白质与已报道植物HMGR氨基酸序列相似性达到63%~70%.由CS-DZc cDNA推导的蛋白质氨基酸序列中具有环氧角鲨烯环化酶(OSCs)特异保守结构域:DCTAE结构域和C末端的2个QW高度保守区,并与已报道植物环阿屯合成酶氨基酸序列相似性达到80%以上.本实验还分别以HMGR-DZh和CS-DZccDNA为探针进行了Southern和Northern杂交分析.Northern杂交分析表明,盾叶薯蓣HMGR-DZh基因的mRNA约为1.8~2 kb,CS-DZc基因的mRNA约为2~2.5 kb.     

Expression of PHGPx in mammalian cells and its antiviral effect against coxsackievirus group B

To express human phospholipid hydroperoxide glutathione peroxidase (PHGPx) in eukaryotic cells and to study its antiviral effect against Coxsackievirus B3m (CVB3m) in vitro, PHGPx cDNA was amplified from a human testis library using specific primers and cloned into expression vector pcDNA3. I/His. Expression of PHGPx was performed in COS-1 cells. The antiviral effect was studied by the treatment of HeLa cells with the recombinant PHGPx. Results showed that the activity of PHGPx expressed in COS-1 cells was 5-fold higher than that in control group, and it inhibited the cytopathic effect on HeLa cells caused by CVB3m. It can be concluded that recombinant PHGPx expressed in COS-1 cells has antiviral effect against CVB3m in vitro.     

一种从基因数据库中识别反义snoRNA基因的新方法

报道一种从国际分子生物学数据库中识别反义ｓｎｏＲＮＡ基因的计算机新方法．介绍新方法的生物学原理及在反义ＳｎｏＲＮＡ新基因发现中的应用．     

Investigations into the perplexing interrelationship of the Genus Takifugu Abe, 1949 (Tetraodontiformes, Tetraodontidae)

The phylogenetic relationships within the genus Takifugu Abe, 1949 (Tetraodontiformes, Tetraodonti- dae) remain unresolved. Because of the use of Takifugu as model organisms, the resolution of these relationships is crucial for the interpretation of evolutionary trends in biology. Pufferfishes of this ge- nus are comprised of a comparatively small number of species and are mainly distributed along the coastal region of the western part of the Sea of Japan and the coastline of China. Mitochondrial gene sequences were employed to test the phylogenetic hypotheses within the genus. Seventeen species of the genus were examined. Molecular phylogenetic trees were constructed using the maximum parsi- mony, neighbor-joining, maximum likelihood and Bayesian methods. Our hypothesis of internal relationships within the genus differs from previous hypotheses. Our results indicate that (1) the genus Takifugu is a monophyletic assemblage; (2) the genus is divided into 6 subgroups based on the mo- lecular data; and (3) there is low genetic diversity among the species within this genus. In addition, speciation within Takifugu appears to be driven by hybridization and isolation by distribution. Our re- sults also suggested that the taxonomy in the genus should be clarified based on both molecular and morphological data.     

光照和黑暗条件下大豆和玉米基因表达差异的初步研究

光照黑暗条件下，植物幼苗的形态建成差异十分明显，以双子叶植物大豆和单子叶植物玉 材料，利用改进的ｍＲＮＡ差异展示技术分析了黄化苗和苗的基因表达的差异，黄化苗和苗基因表达差异可以归纳为“：黄化苗基因特异表达，绿苗基因特异表达，黄化苗基因表达增强，绿苗基因表达增强，黄化革和绿苗基因表达水平和近五咱类型大豆绿苗中基因特异表达类型比黄化苗要多，玉米中则相反，黄化苗基因特异表达类型多于绿苗，试验中还对差异展     

基于偏最小二乘与极大间距准则的微阵列分类

 针对基因表达数据中的高维小样本问题，提出了一种两阶段的识别框架：“偏最小二乘法(PLS)+极大间距准则(MMC）”。该方法首先使用PLS算法提取出带有分类信息的特征，然后使用MMC准则对样本进行分类。在六个公共的基因数据库上与一些常见的基因分类方法相比较，结果显示了该方法对基于基因表达数据的肿瘤分类有效且稳定。     

Isolation of cDNAs Enconding Two Distinct Transcription Factors Binding to DRE cis-acting Element Involved in Cold- and drought-induced Expression of Arabidopsis rd29A Gene

ＩｎｔｒｏｄｕｃｔｉｏｎＳｅｖｅｒｅｅｎｖｉｒｏｎｍｅｎｔａｌｃｈａｎｇｅｓ ,ｓｕｃｈａｓｌｏｗ ｔｅｍｐｅｒａｔｕｒｅ ,ｄｒｏｕｇｈｔａｎｄｈｉｇｈ ｓａｌｔ ,ａｆｆｅｃｔｔｈｅｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｏｆ ｐｌａｎｔｓａｎｄｔｈｅｐｒｏｄｕｃｔｉｖｉｔｙｏｆｃｒｏｐｓ .Ｐｌａｎｔｃｅｌｌｃａｎｎｏｔｏｂｔａｉｎｗａｔｅｒｗｈｅｎｓｕｂｊｅｃｔｅｄｔｏｄｒｏｕｇｈｔｏｒｈｉｇｈ ｓａｌｔｃｏｎｄｉｔｉｏｎ .Ｌｏｗ ｔｅｍｐｅｒａｔｕｒｅａｌｓｏｒｅｄｕｃｅｓｗａｔｅｒｓｔａｔｅｏｆ …     

采用偏最小二乘法的基因-药物共模块识别

首先,将药物二维化学结构转化为数值序列,计算药物之间的皮尔逊相关系数,进而构建药物关联网络;然后,在带有基因网络约束的稀疏偏最小二乘算法的基础上,加入药物关联网络信息,提出伴有基因和药物关联网络正则约束的稀疏偏最小二乘(SGDPLS)算法;最后,将SGDPLS算法应用于基因-药物共模块识别.结果表明:药物关联网络信息的加入能够有效提高所识别的共模块中基因模块与药物模块的相关性,增加共模块的生物可解释性.     

PCR技术在分子生物学中的应用

PCR方法(Polymerase China Reaction),即聚合酶链式反应,又称体外基因倍增,它在分子生物学中有着广泛的应用。文中主要讨论了PCR技术在辅助构建跳跃及连锁文库(Jumping andLinking Library),染色体走步(Chromosome Walking),基因修饰(Rene Modification),重组PCR(Recombinant PCR),足迹法(Footprinting),进行克隆(Cloning)和亚克隆(Subcloning)诸方面的应用,同时指出了PCR技术存在的不足,尚有待于改进。