The structural ensemble of a Holliday junction determined by X-ray scattering interference.
The structural ensemble of a Holliday junction determined by X-ray scattering interference.
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DOI：
10.1093/nar/gkaa509
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发表时间：
2020-08-20
影响因子：
14.9
通讯作者：
Herschlag D
中科院分区：
文献类型：
--
作者：
Zettl T;Shi X;Bonilla S;Sedlak SM;Lipfert J;Herschlag D
DNA四向（霍利迪）连接是基因重组的中心中间体，但其构象和热力学性质的关键方面仍不清楚。虽然多种实验方法已被用来表征在特定的离子条件下的典型的X-形状的构象，这个主题的完整的构象合奏，特别是在低离子条件下，仍然在很大程度上未确定。与以前的研究一致，我们的单分子Förster共振能量转移（smFRET）测量结动力学揭示了在高盐条件下两种状态之间的转换，但smFRET无法确定在低盐和中等盐条件下不同构象或相关状态的广泛集合之间是否存在快速和不可分辨的转换。因此，我们使用了一种新兴的技术，X射线散射干涉法（XSI），直接探测构象合奏的霍利迪交界处在广泛的离子条件。我们的研究结果表明，四路交界处采用平面外的几何形状在低离子条件下，并揭示了构象状态在中间离子条件下以前未检测到的其他方法。我们的研究结果提供了关键的信息，建立一个完整的描述的构象景观的霍利迪交界处，并强调实用的XSI探测构象合奏在广泛的解决方案条件下。
The DNA four-way (Holliday) junction is the central intermediate of genetic recombination, yet key aspects of its conformational and thermodynamic properties remain unclear. While multiple experimental approaches have been used to characterize the canonical X-shape conformers under specific ionic conditions, the complete conformational ensemble of this motif, especially at low ionic conditions, remains largely undetermined. In line with previous studies, our single-molecule Förster resonance energy transfer (smFRET) measurements of junction dynamics revealed transitions between two states under high salt conditions, but smFRET could not determine whether there are fast and unresolvable transitions between distinct conformations or a broad ensemble of related states under low and intermediate salt conditions. We therefore used an emerging technique, X-ray scattering interferometry (XSI), to directly probe the conformational ensemble of the Holliday junction across a wide range of ionic conditions. Our results demonstrated that the four-way junction adopts an out-of-plane geometry under low ionic conditions and revealed a conformational state at intermediate ionic conditions previously undetected by other methods. Our results provide critical information to build toward a full description of the conformational landscape of the Holliday junction and underscore the utility of XSI for probing conformational ensembles under a wide range of solution conditions.
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影响因子：
8.8
作者：
Liu Y;Freeman ADJ;Déclais AC;Wilson TJ;Gartner A;Lilley DMJ
通讯作者：
Lilley DMJ
影响因子：
64.8
作者：
Cox, MM;Goodman, MF;Marians, KJ
通讯作者：
Marians, KJ
DOI：
10.1073/pnas.92.12.5635
发表时间：
1995-06-06
影响因子：
11.1
作者：
BENNETT, RJ;WEST, SC
通讯作者：
WEST, SC
影响因子：
11.4
作者：
DUCKETT, DR;MURCHIE, AIH;LILLEY, DMJ
通讯作者：
LILLEY, DMJ
影响因子：
4.5
作者：
Lescoute, A;Westhof, E
通讯作者：
Westhof, E