Department of Systems Biology, Harvard Medical School , Boston, Massachusetts 02115, United States.
Nano Lett. 2013 Sep 11;13(9):4242-8. doi: 10.1021/nl4019512. Epub 2013 Aug 26.
Nucleic acid nanotechnology has enabled researchers to construct a wide range of multidimensional structures in vitro. Until recently, most DNA-based structures were assembled by thermal annealing using high magnesium concentrations and nonphysiological environments. Here, we describe a DNA self-assembly system that can be tuned to form a complex target structure isothermally at any prescribed temperature or homogeneous condition within a wide range. We were able to achieve isothermal assembly between 15 and 69 °C in a predictable fashion by altering the strength of strand-strand interactions in several different ways, for example, domain length, GC content, and linker regions between domains. We also observed the assembly of certain structures under biocompatible conditions, that is, at physiological pH, temperature, and salinity in the presence of the molecular crowding agent polyethylene glycol (PEG) mimicking the cellular environment. This represents an important step toward the self-assembly of geometrically precise DNA or RNA structures in vivo.
核酸纳米技术使研究人员能够在体外构建各种多维结构。直到最近，大多数基于 DNA 的结构都是通过在高镁浓度和非生理环境下进行热退火来组装的。在这里，我们描述了一种 DNA 自组装系统，该系统可以在很宽的范围内调节到在任何规定的温度或均相条件下形成复杂的目标结构。通过以几种不同的方式改变链-链相互作用的强度，例如结构域长度、GC 含量和结构域之间的连接区，我们能够以可预测的方式在 15 到 69°C 之间实现等温组装。我们还观察到在某些结构在生物相容性条件下的组装，即在生理 pH 值、温度和盐度下，在分子拥挤剂聚乙二醇（PEG）的存在下模拟细胞环境。这代表了朝着在体内自组装几何精确的 DNA 或 RNA 结构迈出的重要一步。
