...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Physics. Condensed Matter >Introducing a model of pairing based on base pair specific interactions between identical DNA sequences
【24h】

Introducing a model of pairing based on base pair specific interactions between identical DNA sequences

机译：基于相同DNA序列之间的碱基对特异性相互作用引入配对模型

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

At present, there have been suggested two types of physical mechanism that may facilitate preferential pairing between DNA molecules, with identical or similar base pair texts, without separation of base pairs. One mechanism solely relies on base pair specific patterns of helix distortion being the same on the two molecules, discussed extensively in the past. The other mechanism proposes that there are preferential interactions between base pairs of the same composition. We introduce a model, built on this second mechanism, where both thermal stretching and twisting fluctuations are included, as well as the base pair specific helix distortions. Firstly, we consider an approximation for weak pairing interactions, or short molecules. This yields a dependence of the energy on the square root of the molecular length, which could explain recent experimental data. However, analysis suggests that this approximation is no longer valid at large DNA lengths. In a second approximation, for long molecules, we define two adaptation lengths for twisting and stretching, over which the pairing interaction can limit the accumulation of helix disorder. When the pairing interaction is sufficiently strong, both adaptation lengths are finite; however, as we reduce pairing strength, the stretching adaptation length remains finite but the torsional one becomes infinite. This second state persists to arbitrarily weak values of the pairing strength; suggesting that, if the molecules are long enough, the pairing energy scales as length. To probe differences between the two pairing mechanisms, we also construct a model of similar form. However, now, pairing between identical sequences solely relies on the intrinsic helix distortion patterns. Between the two models, we see interesting qualitative differences. We discuss our findings, and suggest new work to distinguish between the two mechanisms.
机译：目前，已经提出了两种类型的物理机制，其可以促进DNA分子之间的优先配对，具有相同或相似的基对文本，而不分离碱基对。一种单独依赖于两种分子上的螺旋变形的碱对特定模式的一个机制，过去讨论了两个分子。另一机制提出，碱基对相同的组合物之间存在优先相互作用。我们介绍了一个模型，内置于第二机构，其中包括热拉伸和扭转波动，以及基对特定螺旋扭曲。首先，我们考虑弱配对相互作用或短分子的近似。这产生了能量对分子长度的平方根的依赖性，这可以解释最近的实验数据。然而，分析表明该近似在大DNA长度不再有效。在第二近似，对于长分子，我们定义了两个用于扭转和拉伸的适配长度，配对相互作用可以限制螺旋障碍的累积。当配对相互作用足够强时，适应长度都是有限的;然而，当我们减少配对强度时，拉伸适应长度保持有限但扭转一个变得无限。第二州坚持对配对强度的任意弱值;建议，如果分子足够长，则将配对能量尺寸为长度。为了探测两个配对机制之间的差异，我们还构造了类似形式的模型。然而，现在，相同序列之间的配对单独依赖于内在螺旋失真模式。在两种模型之间，我们看到有趣的定性差异。我们讨论了我们的调查结果，并建议在两个机制之间区分新的工作。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号