Centre for Biological Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
ACS Nano. 2012 Apr 24;6(4):3604-13. doi: 10.1021/nn300718z. Epub 2012 Apr 2.
DNA has been widely exploited for the self-assembly of nanosized objects and arrays that offer the potential to act as scaffolds for the spatial positioning of molecular components with nanometer precision. Methods that allow the targeting of components to specific locations within these structures are therefore highly sought after. Here we report that the triplex approach to DNA recognition, which relies on the specific binding of an oligonucleotide within the major groove of double-helical DNA, can be exploited to recognize specific loci within a DNA double-crossover tile and array, a nanostructure assembled by crossover strand exchange. The oligonucleotide can be targeted to both crossover and non-crossover strands and, surprisingly, across the region spanning the crossover junction itself. Moreover, by attaching biotin to the end of the oligonucleotide, we show that streptavidin molecules can be recruited to precise locations within a DX array, with an average spacing of 31.9 (±1.3) nm. This is a promising approach that could be exploited to introduce other components compatible with oligonucleotide synthesis into the wide variety of DNA nanostructures assembled by crossover strand exchange, such as those generated by DNA origami.
DNA 已被广泛用于纳米级物体和阵列的自组装，这些物体和阵列有可能作为分子组件的空间定位支架，实现纳米级精度的定位。因此，人们迫切需要能够将组件靶向到这些结构内特定位置的方法。在这里，我们报告说，依赖于寡核苷酸在双链 DNA 大沟内的特异性结合的 DNA 识别三联体方法可用于识别 DNA 双交叉瓦片和阵列内的特定位置，DNA 双交叉瓦片和阵列是通过交叉链交换组装的纳米结构。寡核苷酸可以靶向交叉和非交叉链，并且令人惊讶的是，还可以靶向跨越交叉连接点本身的区域。此外，通过将生物素连接到寡核苷酸的末端，我们证明链霉亲和素分子可以被招募到 DX 阵列内的精确位置，平均间距为 31.9(±1.3)nm。这是一种很有前途的方法，可以将与寡核苷酸合成兼容的其他组件引入通过交叉链交换组装的各种 DNA 纳米结构中，例如通过 DNA 折纸术生成的纳米结构。
