Fabrication of Hierarchic DNA Nano-Array based on Stretched DNA

DNA微阵列技术是一项非常重要的基础技术。对于高通量分析，DNA阵列的高密度和高集成度是必需的。然而，传统的光刻技术无法实现小于20mm的DNA斑点密度。因此，我们尝试采用FISH（荧光原位杂交）方法，以拉伸的单个DNA分子作为DNA阵列的模板，开发100 nm距离的DNA排列技术。我们证明了序列为40mer并有20mer重叠的寡核苷酸可以形成多聚体。从线性到圆形的结构变化依赖于金属阳离子。这一结果表明我们可以通过添加阳离子来设计DNA结构。为了控制DNA结构，我们研究了阳离子浓度诱导结构变化和与阳离子特异性相互作用的序列。制备了含有或不含a链、a链位置不同的四种寡核苷酸。每种多组分在TE中提供不同的电泳凝胶模式，TE含有Na^+或Mg^<2+>。结果表明，金属离子使DNA多组合体的结构由线性转变为圆形。

The DNA micro-array method is very important fundamental technique. For high-through put analysis, the high density and high degree of integration of a DNA array is required. However, the DNA spots density less than 20 mm cannot be achieved by using conventional photolithography and spotter. Therefore we attempted to develop DNA arrangement technology with 100 nm distance by the FISH (Fluorescence In-situ Hybridization) method based on a stretched single DNA molecule as a template for the DNA array.We demonstrated that oligonucleotides whose sequences were 40mer and overlapped by 20mer were formed multi-assemblies. The structural change from a linear to a circle was dependent on metal cations. This result suggested that we could design DNA structures by adding cations. In order to control the DNA structures, we investigated the concentration of cations to induce structural changes and sequences to interact with cations specifically. Four sorts of oligonucleotides, which contained A-tract or not, or A-tract position was different, were prepared. Each of the multi-assemblies provided different electrophoretic gel patterns in TE, TE containing Na^+ or Mg^<2+>. It concluded that metal ion changed the structure of DNA multi-assemblies from linear to circular forms.