A study of DNA tube formation mechanisms using 4-, 8-, and 12-helix DNA nanostructures
A study of DNA tube formation mechanisms using 4-, 8-, and 12-helix DNA nanostructures
复制标题
DOI：
10.1021/ja058145z
复制
发表时间：
2006-04-05
影响因子：
15
通讯作者：
Yan, H
中科院分区：
文献类型：
--
作者：
Ke, YG;Liu, Y;Yan, H
本文描述了一类新的包含4、8和12个螺旋的矩形DNA纳米结构（DNA瓦片）的设计与特性。还研究了这三种瓦片的自组装形态。设计这组DNA纳米结构的动机源于想要制造出包含可编程尺寸的周期性空腔的DNA晶格，并研究DNA管形成的机制。通过三种不同瓦片的组合以及三种粘性末端连接策略，研究了九种组装情形。原子力显微镜（AFM）成像显示出具有不同空腔尺寸、晶格形态和取向的自组装结构。六个样本仅显示管的形成，两个样本既显示二维晶格（>2微米）又显示管，一个样本仅显示二维晶格而无管。我们发现，较低的维度各向异性、较弱的连接以及波纹状设计有利于大型二维阵列的形成，而相反的情况（较高的各向异性、较强的连接以及无波纹设计）则有利于管的形成。我们从平衡时的能量平衡以及在组装早期扩散受限的横向晶格生长与晶格波动形成管之间的动力学竞争的角度来讨论这些观察结果。本文所展示的DNA纳米结构及其自组装不仅为纳米级材料的组织提供了新的模板支架，还可能为研究其他自组装系统提供有用信息。
This paper describes the design and characterization of a new family of rectangular-shaped DNA nanostructures (DNA tiles) containing 4, 8, and 12 helices. The self-assembled morphologies of the three tiles were also investigated. The motivation for designing this set of DNA nanostructures originated from the desire to produce DNA lattices containing periodic cavities of programmable dimensions and to investigate the mechanism of DNA tube formation. Nine assembly scenarios have been investigated through the combination of the three different tiles and three sticky end association strategies. Imaging by atomic force microscopy (AFM) revealed self-assembled structures with varied cavity sizes, lattice morphologies, and orientations. Six samples show only tube formation, two samples show both 2D lattices (> 2 mu m) and tubes, and one sample shows only 2D lattices without tubes. We found that a lower the dimensional anisotropy, weaker connection, and corrugated design favor the large 2D array formation, while the opposite (higher the anisotropy, stronger connection, and uncorrugated design) favors tube formation. We discuss these observations in terms of an energy balance at equilibrium and the kinetic competition between diffusion-limited lateral lattice growth versus fluctuation of the lattice to form tubes at an early stage of the assembly. The DNA nanostructures and their self-assembly demonstrated herein not only provide a new repertoire of scaffolds to template the organization of nanoscale materials, but may also provide useful information for investigating other self-assembly systems.