The flexibility of DNA double crossover molecules
The flexibility of DNA double crossover molecules
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DOI：
10.1016/s0006-3495(03)75110-8
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发表时间：
2003-06-01
影响因子：
3.4
通讯作者：
Seeman, NC
中科院分区：
文献类型：
--
作者：
Sa-Ardyen, P;Vologodskii, AV;Seeman, NC
双交叉分子是包含由两个双螺旋臂连接的两个霍利迪连接点的DNA结构。双交叉分子有几种类型，根据其螺旋轴的相对方向（平行或反平行）以及两个交叉点之间双螺旋半圈的数量（偶数或奇数）来区分。它们作为减数分裂的中间产物被发现，并且在结构DNA纳米技术中被广泛用于构建一维和二维阵列以及一种DNA纳米机械装置。鉴于平行双螺旋分子通常表现不佳，我们将重点放在反平行分子上；在交叉点之间具有偶数个半圈的反平行分子（称为DAE分子）在连接时会产生一条报告链，这有助于在连接环化分析中对其进行表征。因此，我们通过连接闭合实验估算了反平行DNA双交叉分子的柔韧性。我们能够表明，这些分子的刚性大约是线性双链DNA的两倍。
Double crossover molecules are DNA structures containing two Holliday junctions connected by two double helical arms. There are several types of double crossover molecules, differentiated by the relative orientations of their helix axes, parallel or antiparallel, and by the number of double helical half-turns (even or odd) between the two crossovers. They are found as intermediates in meiosis and they have been used extensively in structural DNA nanotechnology for the construction of one-dimensional and two-dimensional arrays and in a DNA nanomechanical device. Whereas the parallel double helical molecules are usually not well behaved, we have focused on the antiparallel molecules; antiparallel molecules with an even number of half-turns between crossovers (termed DAE molecules) produce a reporter strand when ligated, facilitating their characterization in a ligation cyclization assay. Hence, we have estimated the flexibility of antiparallel DNA double crossover molecules by means of ligation-closure experiments. We are able to show that these molecules are approximately twice as rigid as linear duplex DNA.