Modifying the surface features of two-dimensional DNA crystals
Modifying the surface features of two-dimensional DNA crystals
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DOI：
10.1021/ja982824a
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发表时间：
1999-02-10
影响因子：
15
通讯作者：
Seeman, NC
中科院分区：
文献类型：
--
作者：
Liu, FR;Sha, RJ;Seeman, NC
DNA 双交叉 (DX) 分子是刚性 DNA 基序，包含在两个不同点连接的两个双螺旋。可以从 DX 分子形成氢键二维晶体并通过原子力显微镜 (AFM) 观察这些阵列 [Winfree, E.;刘，F。洛杉矶温茨勒； Seeman，北卡罗来纳州《自然》，1998 年，394，539-544]。将阵列固定在一起的粘性末端可以是不同的，以便在晶体中包含分子的不同周期性排列。包含设计为从晶体平面突出的额外 DNA 发夹提供了在 AFM 图像中很容易检测到的地形标记：通过使用这些标记，可以在晶体表面上以预测的间距产生条纹。这里提出的实验表明，可以通过酶促和非酶促程序来修改这些模式。我们表明可以从阵列中定量去除含有限制性位点的发夹。我们还证明，从阵列突出的粘性末端可以连接到包含其补体的发夹。此外，无论是在溶液中还是在云母表面沉积之后，都可以通过氢键将发夹退火至晶体阵列。修改这些阵列的能力增加了可以从一组初始 DX 组件生成的模式的多样性。因此，可以通过多种方式修改单个阵列，从而改变其物理或化学特征。
DNA double-crossover (DX) molecules are rigid DNA motifs that contain two double helices linked at two different points. It is possible to form hydrogen-bonded two-dimensional crystals from DX molecules and to observe those arrays by atomic force microscopy (AFM) [Winfree, E.; Liu, F.; Wenzler, L. A.; Seeman, N. C. Nature 1998, 394, 539-544]. The sticky ends that hold the arrays together can be varied, so as to include diverse periodic arrangements of molecules in the crystal. The inclusion of extra DNA hairpins designed to protrude from the plane of the crystal provides a topographic label that is detected readily in AFM images: By using these labels, it is possible to produce stripes at predicted spacings on the surface of the crystal. The experiments presented here demonstrate that it is possible to modify these patterns, by both enzymatic and nonenzymatic procedures. We show that a hairpin containing a restriction site can be removed quantitatively from the array. We also demonstrate that a sticky end protruding from the array can be ligated to a hairpin containing its complement. In addition, it is possible to anneal a hairpin to the crystalline array by hydrogen bonding, both in solution and after deposition on a mica surface. The ability to modify these arrays increases the diversity of patterns that can be produced from an initial set of DX components. Thus, a single array can be modified in a large number of ways that can alter its physical or chemical features.