Single-molecule measurements of the persistence length of double- stranded RNA
Single-molecule measurements of the persistence length of double- stranded RNA
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DOI：
10.1529/biophysj.104.052811
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发表时间：
2005-04-01
影响因子：
3.4
通讯作者：
Dekker, NH
中科院分区：
文献类型：
--
作者：
Abels, JA;Moreno-Herrero, F;Dekker, NH
在过去的几年里，双链RNA（dsRNA）在细胞生命周期中的作用比以前预期的要大得多，这一点变得越来越明显。许多蛋白质，包括解旋酶、聚合酶和核酸酶与dsRNA的双螺旋特异性地相互作用。为了理解这些dsRNA-蛋白质相互作用的详细性质，需要充分表征dsRNA的（生物）化学、静电和机械性质。我们目前的测量的持续长度的双链RNA使用两种不同的单分子技术：磁镊和原子力显微镜。我们推导出的平均持久长度为63.8 +/- 6 0.7 nm的长dsRNA分子的力延伸测量与磁镊子。我们提出了原子力显微镜图像的dsRNA，并展示了一种新的方法来分析这些，这产生了一个独立的，但一致的值为62 +/- 2 nm的持久性长度。这些用于dsRNA分析的单分子技术的引入为dsRNA-蛋白质相互作用的真实的实时定量分析开辟了道路。
Over the past few years, it has become increasingly apparent that double- stranded RNA ( dsRNA) plays a far greater role in the life cycle of a cell than previously expected. Numerous proteins, including helicases, polymerases, and nucleases interact specically with the double helix of dsRNA. To understand the detailed nature of these dsRNA- protein interactions, the ( bio)chemical, electrostatic, and mechanical properties of dsRNA need to be fully characterized. We present measurements of the persistence length of dsRNA using two different single- molecule techniques: magnetic tweezers and atomic force microscopy. We deduce a mean persistence length for long dsRNA molecules of 63.8 +/- 6 0.7 nm from force extension measurements with the magnetic tweezers. We present atomic force microscopy images of dsRNA and demonstrate a new method for analyzing these, which yields an independent, yet consistent value of 62 +/- 2 nm for the persistence length. The introduction of these single- molecule techniques for dsRNA analysis opens the way for real- time, quantitative analysis of dsRNA- protein interactions.