嗜麦芽假单胞菌质粒pSH1的限制图谱及km~r标记的克隆

对嗜麦芽假单胞菌Ｐ２菌株（ＰｓｅｕｄｏｍｏｎａｓｍａｌｔｏｏｈｉｌｉａＰ２）的质粒ｐＳＨ１进行了限制酶切分析，确定了ＢｇｌⅡ、ＥｃｏＲⅠ、ＰｓｔⅠ、ＸｂａⅠ、ＢａｍＨⅠ、ＢｇｌⅠ、及ＰｖｕⅡ共７种限制性内切酶在ｐＳＨ１、质粒上的切割位点，前４种酶均为单一切点；后３种依次为２、７、５个切点．通过双酶切和部分酶切的方法绘制了ｐＳＨ１质粒的限制酶切图谱．将ｐＧＰ１－２质粒上的卡那霉素抗性基因（ｋｍｒ）片段插入ｐＳＨ１，获得了重组质粒ｐＳＨ２．ｐＳＨ２是由ｐＧＰ１－２质粒上大小为２．９０ｋｂ的ＤＮＡ片段（含ｋｍｒ）和ｇｈＨ１经ＢａｍＨⅠ－ＰｓｔⅠ双酶切产生５．７０ｋｂ大片段组成，它能够重新转化到喀麦芽假单胞菌受体（ｋｍｒ）中，其ｋｍｒ标记能够得到稳定的表达．     

人脊髓灰质炎病毒感染诱发Vero细胞凋亡的研究

用人脊髓灰质炎病毒分别感染Ｖｅｒｏ细胞和稳定表达ｐ３５基因的Ｖｅｒｏ３５细胞，经细胞核ＤＡＰＩ染色，细胞ＤＮＡ琼脂糖电泳和ＴＤＴ生物素原位标记等方法证实病毒感染的细胞具有典型的凋亡细胞学特征和生物化学特征．实验结果表明人脊髓灰质炎病毒感染Ｖｅｒｏ细胞诱发的细胞死亡能被昆虫杆状病毒凋亡抑制基因ｐ３５抑制，为ＩＣＥ类蛋白水解酶途径的细胞凋亡．     

抑制性消减杂交方法的建立

为建立研究基因表达差异的抑制性消减杂交（SSH）方法，以未加诱导剂处理的结肠癌LoVo细胞提取的mRNA为模板合成的cDNA作为驱赶子（driver)，联合使用10.0μmol/LATRA和0.1μmol/L1,25-(OH)2D3诱导2d的LoVo细胞提取的mRNA为模板合成的cDNA作为测试子（tester)进行SSH实验，结果为：消减产物与未消减样品（对照）在琼脂糖凝胶电泳图谱上明显不同，前者可见一些扩增条带，其大小范围在100-1000bp之间，本实验说明SSH方法对于识别差异表达的基因具有高效性。     

金属离子和热激处理对菊芋(Helianthus tuberosus L.)类金属硫蛋白基因htMT2表达的影响

使用不同金属离子及热激对菊芋进行了处理，并对菊芋不同组织器官中类金属硫蛋白基因(htMT2)mRNA水平的变化进行了研究．结果表明，htMT2在根中不表达，而且其表达不受金属离子的影响．Cu^2 降低叶中htMT2的表达，Cu^2 浓度与茎、叶中的htMT2 mRNA水平呈负相关性．在低浓度范围内，Zn^2 浓度与茎、叶中的htMT2 mRNA水平呈正相关性，而在高浓度范围内，Zn^2 浓度与htMT2 mRNA水平呈负相关性．Ca^2 对叶中htMT2表达的影响与Zn^2 的作用相似，但Ca^2 诱导茎中htMT2 mRNA水平升高．热激处理对不同组织中htMT2的表达无显著影响．研究的结果表明，htMT2表达受金属离子影响的特征与植物MT基因一致，进一步证实了我们前期工作中分离到的htMT2是一个新的植物MT基因．     

Epigenetic Genome Mining of an Endophytic Fungus Leads to the Pleiotropic Biosynthesis of Natural Products

The small‐molecule biosynthetic potential of most filamentous fungi has remained largely unexplored and represents an attractive source for the discovery of new compounds. Genome sequencing of Calcarisporium arbuscula, a mushroom‐endophytic fungus, revealed 68 core genes that are involved in natural product biosynthesis. This is in sharp contrast to the predominant production of the ATPase inhibitors aurovertin B and D in the wild‐type fungus. Inactivation of a histone H3 deacetylase led to pleiotropic activation and overexpression of more than 75 % of the biosynthetic genes. Sampling of the overproduced compounds led to the isolation of ten compounds of which four contained new structures, including the cyclic peptides arbumycin and arbumelin, the diterpenoid arbuscullic acid A, and the meroterpenoid arbuscullic acid B. Such epigenetic modifications therefore provide a rapid and global approach to mine the chemical diversity of endophytic fungi.     

Mesoporous Silica Nanoparticles Decorated with Carbosilane Dendrons as New Non‐viral Oligonucleotide Delivery Carriers

A novel nanosystem based on mesoporous silica nanoparticles covered with carbosilane dendrons grafted on the external surface of the nanoparticles is reported. This system is able to transport single‐stranded oligonucleotide into cells, avoiding an electrostatic repulsion between the cell membrane and the negatively charged nucleic acids thanks to the cationic charge provided by the dendron coating under physiological conditions. Moreover, the presence of the highly ordered pore network inside the silica matrix would make possible to allocate other therapeutic agents within the mesopores with the aim of achieving a double delivery. First, carbosilane dendrons of second and third generation possessing ammonium or tertiary amine groups as peripheral functional groups were prepared. Hence, different strategies were tested in order to obtain their suitable grafting on the outer surface of the nanoparticles. As nucleic acid model, a single‐stranded DNA oligonucleotide tagged with a fluorescent Cy3 moiety was used to evaluate the DNA adsorption capacity. The hybrid material functionalised with the third generation of a neutral dendron showed excellent DNA binding properties. Finally, the cytotoxicity as well as the capability to deliver DNA into cells, was tested in vitro by using a human osteoblast‐like cell line, achieving good levels of internalisation of the vector DNA/carbosilane dendron‐functionalised material without affecting the cellular viability.