利用CTAB法提取蝴蝶兰的基因组DNA

利用CTAB法对蝴蝶兰的根、叶、花等不同部位进行基因组DNA的提取，然后分别用紫外分光光度法和琼脂糖凝胶电泳法检测DNA的质量，结果表明，3个部位都可以获得较完整的基因组DNA，电泳条带清晰，无拖尾现象．其中根部提取的DNA纯度最高，OD260／OD280为1．6545；其次为叶，OD260／OD280为1．5351；花的DNA纯度最低，仅为1．3820．     

植物抗病毒基因工程研究进展

近年来 ,植物抗病毒基因工程研究进展迅速 ,本文就这方面的发展进行了综述 ,重点介绍了外壳蛋白基因、复制酶基因以及运动蛋白基因介导的抗性等策略的抗病机理及其应用     

DNA与识别分子相互作用的电化学研究

介绍了DNA与识别分子相互作用电化学研究的原理,对DNA与各种类型的分子相互作用的电化学研究等方面的最新进展进行了评述。     

原子力显微镜观察DNA与内切酶的相互作用

原子力显微镜是观察DNA与内切酶相互作用比较有效的研究技术。实验中,首先把不同种类的内切酶与DNA在含有钙离子的缓冲液中培育30 min,再通过原子力成像观察其相互作用后的复合物形貌。结果表明,二聚体内切酶EcoRV会结合到λ-DNA的单个识别位点,最终形成珠串状结构,而且对DNA有弯曲作用;另一类型四聚体内切酶BspMI除了可以结合λ-DNA的单个位点外,还可以结合2个识别位点而形成圆环状结构。此结果可以直观地观察到两种内切酶与DNA的作用形态,同时对DNA的弯曲与成环等结构给出直接证据。最后给出两种内切酶与DNA相互作用的模型图。     

建议限制酶及其相关酶采用新的表达形式 ——兼与王雪莹和郭国庆先生商榷

《编辑学报》2012年第3期刊载了王雪莹和郭国庆的论文《限制性核酸内切酶的规范表达》[1],正如该文作者所提及的,在我国的科技期刊中普遍存在限制性核酸内切酶(下简称限制酶)的表达比较混乱且不规范的现象。同时作者对限制酶的命名原则作了详细介绍,并给出了其规范的表达形式;但是,由于限制酶及其相关酶有     

mtDNA analysis of the human remains buried in the sarcophagus of Federico II

The sarcophagus containing the remains of Federico II, located in the Cathedral of Palermo (Sicily, Italy), was opened on 1998 to perform a multidisciplinary survey [1]. Next to the remains of Federico II and in close contact with them were laying two other skeletons belonging, according to historical records, to Pietro II di Aragona and to an anonymous person (“The Third Individual”), probably a woman. The bones appeared severely deteriorated. Chemical analysis performed on bone samples excluded that the bodies underwent some kind of embalming process. The analysis of mtDNA from bone samples taken from the three skeletons was successful in only one of the two labs involved. The HVR1-mtDNA sequence (region: from nt 16,035 to nt 16,395), obtained from the bone samples of Federico II and “The Third Individual” appear identical but bear double peaks at the same nucleotide positions, suggesting mixing (i.e. contamination) of different mtDNA types. The HVR1 sequence obtained from the bone sample of Pietro II di Aragona does not present double peaks and differ from the Cambridge Reference Sequence (CRS) at six nucleotide positions. Cloning experiment of the Federico II amplicon demonstrated that the mixed mtDNA types are only two: one identical to CRS, the other identical to the sequence of Pietro II di Aragona. A reconstruction of these data are proposed in the Discussion. Due to the problematic context in which this study was carried out (mixed and deteriorated biological material, failure to replicate results in two different labs), our results and reconstruction can only be offered on a tentative basis. It is hoped that the data presented in this study will reveal useful, for future comparison, if further molecular genetics research will be carried out on the royal dynasties that ruled Sicily in the early centuries of the past millennium.     

南阳牛血液基因组DNA提取与ANGPTL4基因的PCR扩增

采集20例南阳牛的血液,采用酚/氯仿法分离白细胞提取基因组DNA,并且对ANGPTL4基因部分序列(677～998 bp)PCR扩增条件进行了优化。结果表明,获得的牛基因组DNA经0.8%琼脂糖凝胶电泳检测,主条带清晰,表明获得的南阳牛基因组DNA可以用于后续实验;以所提取的基因组DNA为模板,优化ANGPTL4基因片段扩增的条件,结果表明,最理想的PCR扩增条件是模板量为2μL(50 mg/L),Taq聚合酶(5 u/μL)的量为0.8μL,退火温度为56℃,循环次数为35次。     

DNA的二维图表示

给出了新的DNA二维图表示,证明了该表示是非退化的,并提出了一种新的DNA相似度计算方法.     

Protective effect of DNA-mediated immunization with liposome-encapsulated GRA4 against infection of Toxoplasma gondii

The dense granule protein 4 (GRA4) is a granular protein from Toxoplasma gondii, and is a candidate for vaccination against this parasite. In this study, the plasmid pcDNA3. 1-GRA4 (pGRA4), encoding for the GRA4 antigen, was incorporated by the dehydration-rehydration method into liposomes composed of 16 mmol/L egg phosphatidylcholine (PC), 8 mmol/L dioleoyl phosphatidylethanolamine (DOPE), and 4 mmol/L 1,2-diodeoyl-3-(trimethylammonium) propane (DOTAP). C57BL/6 mice and BALB/c mice were immunized intramuscularly three times with liposome-encapsulated pGRA4 to determine whether DNA immunization could elicit a protective immune response to T. gondii. Enzyme-linked immunosorbent assay (ELISA) of sera from immunized mice showed that liposome-encapsulated pGRA4 generated high levels of IgG antibodies to GRA4. Production of primary interferon (IFN)-γ and interleukin (IL)-2 in GRA4-stimulated splenocytes from vaccinated mice suggested a modulated Th1-type response. 72.7% of C57BL/6 mice immunized with liposome-encapsulated pGRA4 survived the challenge with 80 tissue cysts of ME49 strain, whereas C57BL/6 mice immunized with pGRA4 had only a survival rate of 54.5%. When immunized BALB/c mice were intraperitoneally challenged with 103 tachyzoites of the highly virulent RH strain, the survival time of mice immunized with liposome-encapsulated pGRA4 was markedly longer than that of other groups. Our observations show that liposome-encapsulated pGRA4 enhanced the protective effect against infection of T. gondii.