二维DNA晶体的多重熔解过程研究

The Melting behavior of 2D-DNA Lattices

可人工编程设计的刚性DNA分子瓦(DNAtile)中的DX分子(double-crossover,双交叉)能自组装形成二维DNA晶体。将含有二维DNA晶体的缓冲溶液程序升温,用紫外鄄可见分光光度计在260nm处测定二维DNA晶体的熔解曲线,观测到了DNA晶体的多重熔解过程。AFM显微镜的研究也观测到了二维DNA晶体受热解体后的图像,表明二维DNA晶体的熔解过程首先发生在DX分子瓦间的黏性末端,然后是DX分子瓦的解体,由此推测,在DNA晶体生长过程中单链DNA相互结合成分子瓦后,分子瓦进一步自组装成晶体。

The synthetic sequences are designed to self-assemble into four double-crossover (DX) DNA tiles. The,sticky ends' of these tiles that associate according to Watson-Crick's base pairing are programmed to build up specific periodic patterns upto tens of microns. UV thermal scans were carried out with increasing the temperature of the 2D-DNA buffer solution. Melting curves were collected at 260 nm. According to the melting process and AFM imaging, we infer that the DNA lattices were first split into 4 DNA DX tiles, then into single oligonucleotides. It is proposed from the melting process that the 22 oligonucleotides self-assemble into four DNA tiles, then into the 2D-DNA crystal.