结构洞察四重复-双重复3'接口形成的Telomeric重复:一个潜在的分子目标
Irene Russo Krauss1, Sneha Ramaswamy2, Stephen Neidle2
1Department of Chemical Sciences, University of Naples Federico II , I-80126 Napoli, Italy.
Journal of the American Chemical Society
|January 6, 2016
概括
研究人员研究了G四重复和人类端粒DNA之间的3'接口. 结构分析揭示了TAT三合体平台,为选择性小分子结合提供了潜在的目标.
科学领域:
- 结构生物学
- 生物化学
- 分子生物学
背景情况:
- 端粒是真核染色体的保护帽,富含氨酸 (G) 丰富的序列,可以形成G四重复结构.
- G四重复和双重复 DNA 在端粒3'端共存,形成复杂的结点.
- 用小分子准这些端粒结构是癌症治疗的策略, 但选择性仍然是一个挑战.
研究的目的:
- 阐明平行G四重复和人类端粒双重复的3'接口的结构基础.
- 为了确定小分子在端粒G-四重复-双重复交叉点的潜在结合点.
- 探索开发针对端粒维持的选择性治疗药物的策略.
主要方法:
- 使用X射线结晶学来确定高分辨率的G-四倍体-双倍体DNA结.
- 用分子建模和in silico对接来研究配体相互作用.
- 使用与端粒双重序列连接的G-四重复构造支架组装了DNA结构.
主要成果:
- 得到了3'四重复-双重复结的详细结构,显示了并行G-四重复和B-形式双重复DNA的同轴堆叠.
- 确定了一个保存的TAT三合体平台,介于G-四重复和双重复区域之间的基层堆叠.
- 在缺乏配体的情况下,TAT三合体会在接口上阻断结合;然而,单个核酸的重新排列会产生稳定的结合口袋.
结论:
- TAT三元平台是端粒G-四重复-双重复接口的一个关键结构特征.
- 这种接口为开发旨在干扰端粒功能的选择性小分子提供了一个独特的目标.
- 结构修改可以为向药物设计创建特定的口袋,从而提高G-四重复结合剂的选择性.
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