• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Nano letters >Exploring Nucleosome Unwrapping Using DNA Origami
【24h】

Exploring Nucleosome Unwrapping Using DNA Origami

机译：使用DNA折纸探索核小体展开

获取原文
获取原文并翻译 | 示例
       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We establish a DNA origami based tool for quantifying conformational equilibria of biomolecular assemblies as a function of environmental conditions. As first application, we employed the tool to study the salt-induced disassembly of nucleosome core particles. To extract binding constants and energetic penalties, we integrated nucleosomes in the spectrometer such that unwrapping of the nucleosomal template DNA, leading from bent to more extended states was directly coupled to the conformation of the spectrometer. Nucleosome unwrapping was induced by increasing the ionic strength. The corresponding shifts in conformation equilibrium of the spectrometer were followed by direct conformation imaging using negative staining TEM and by FRET read out after gel electrophoretic separation of conformations. We find nucleosome dissociation constants in the picomolar range at low ionic strength (n mM MgCl2), in the nanomolar range at intermediate ionic strength (n mM MgCl2 with 0.5-1 M NaCl) and in the micromolar range at larger ionic strength (11 mM MgCl2 with >= 1.5 M NaCl). Integration of up to four nucleosomes stacked side-by-side, as it might occur within chromatin fibers, did not appear to affect the salt-induced unwrapping of nucleosomes. Presumably, such stacking interactions are already effectively screened at the nucleosome unwrapping conditions. Our spectrometer provides a modular platform with a direct read out to study conformational equilibria for targets from small biomolecules up to large macromolecular assemblies.
机译：我们建立了一个基于DNA折纸的工具，可以根据环境条件量化生物分子组装的构象平衡。作为第一个应用程序，我们使用了该工具来研究盐诱导的核小体核心颗粒的分解。为了提取结合常数和高能罚分，我们将核小体整合到光谱仪中，从而使核糖体模板DNA的解缠（从弯曲状态延伸到更扩展的状态）直接与光谱仪的构象相关。通过增加离子强度来诱导核小体解缠。光谱仪的构象平衡发生相应变化，然后使用负染色TEM直接构象成像，并在凝胶电泳分离构象后读出FRET。我们发现在低离子强度（n mM MgCl2）的皮摩尔范围内的核小体解离常数，在中等离子强度（nmM MgCl2与0.5-1 M NaCl）的纳摩尔范围内和在较大离子强度（11 mM）的微摩尔范围内含> = 1.5 M NaCl的MgCl2）。多达四个并排堆叠的核小体的整合（可能会发生在染色质纤维内）似乎并未影响盐诱导的核小体解缠。据推测，这种堆积相互作用已经在核小体解缠条件下得到了有效筛选。我们的光谱仪提供了一个模块化平台，可直接读出以研究从小生物分子到大分子组装体的构象平衡。

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