A contractile DNA machine
A contractile DNA machine
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DOI：
10.1002/anie.200800476
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发表时间：
2008-01-01
影响因子：
16.6
通讯作者：
Yan, Jie
中科院分区：
文献类型：
--
作者：
Lubrich, Daniel;Lin, Jie;Yan, Jie
DNA是一种非常适合在纳米尺度上建造结构和机器的材料。[1]分子DNA机器由离子条件、DNA水解或DNA本身的变化提供动力。[2-11] DNA驱动的DNA机器的想法是通过构建DNA镊子引入的。[12]分子机器在分子规模的生产、合成和医学方面的应用前景广阔。本文报道的收缩DNA机器（CDM）将DNA杂交能量转换成纳米和微米范围内的受控收缩运动。其设计的一个重要元素是长单链（ss）DNA分子。这种分子以前曾被用于构建一维、[13-15]二维、[16-19]和三维[20] DNA结构。CDM的设计如图1所示。这个分子机器是一个分子镊子单元的许多拷贝的线性组装。每个镊子单元由一个长ss DNA分子的重复单元作为模板。图1a显示了如何通过使用滚环复制来合成该模板。[21]图1b显示了处于完全扩展状态的CDM的一部分。与模板杂交的20个核苷酸（nt）分别是左和右镊子臂;每个臂的32个nt保留为ss。手臂进行开合运动。间隔子链以其整个95 nt与模板杂交。它的作用是充分分离相邻单元，以防止镊子之间的相互作用。一个4 nt长的ss铰链段，它是模板的一部分，连接每个镊子单元的两个臂，并提供足够的灵活性。135个双链（ds）和4个ss nt翻译成每个完全延伸重复的长度约为48 nm。所有镊子单元闭合的收缩状态如图1d所示。在其闭合状态下的重复单元的长度预期为约36 nm，32 nm由间隔片段贡献，4 nm（并排放置的两个双螺旋的宽度）由两个镊子臂贡献。通过使用两个“燃料”股，一个打开股和一个关闭股，镊子可以在打开状态（图1 c1）和关闭状态（图1 c4）之间循环。加入后，ss闭合链与镊子右臂的ss片段杂交。然后它开始与左臂的ss段相互作用。这导致镊子开始闭合过程。合作社闭幕式
DNA is a material well suited to the building of structures and machines at the nanoscale.[1] Molecular DNA machines powered by changes in ionic conditions, DNA hydrolysis, or DNA itself have been constructed.[2–11] The idea of DNA-powered DNA machines was introduced by building DNA tweezers.[12] Molecular machines hold much promise for applications in molecular-scale production, synthesis, and medicine. The contractile DNA machine (CDM) reported here transduces DNA hybridization energy into controlled contraction movements in the nano-and micrometer ranges. An important element of its design is a long single-stranded (ss) DNA molecule. Such molecules have previously been used to build one-,[13–15] two-,[16–19] and three-dimensional [20] DNA structures.The design of the CDM is shown in Figure1. This molecular machine is a linear assembly of many copies of a molecular tweezers unit. Each tweezers unit is templated by one repeat unit of a long ss DNA molecule. Figure 1a shows how this template is synthesized by using rolling-circle replication.[21] Figure 1b shows part of the CDM in its fully extended state. Hybridized to the template with 20 nucleotides (nt) each are left and right tweezers arms; 32 nt of each arm remain ss. The arms perform an open–close movement. The spacer strand hybridizes to the template with its entire 95nt. Its role is to separate adjacent units sufficiently to prevent interactions between tweezers. A 4-nt-long ss hinge segment, which is part of the template, connects the two arms of each tweezers unit and provides sufficient flexibility. The 135 double-stranded (ds) and four ss nt translate into a length of approximately 48nm per fully extended repeat. The contracted state in which all tweezers units are closed is shown in Figure 1d. The length of a repeat unit in its closed state is expected to be around 36 nm, 32 nm being contributed by the spacer segment and 4 nm (the width of two double helices lying side by side) by the two tweezers arms. By using two “fuel” strands, an opening strand and a closing strand, the tweezers can be cycled between an open state (Figure 1 c1) and a closed state (Figure 1 c4). After being added, the ss closing strand hybridizes to the ss segment of the right arm of the tweezers. It then starts interacting with the ss segment of the left arm. This causes the tweezers to commence the closing process. The cooperative closing