转录介质复合体的子单元架构和功能模块重组
Kuang-Lei Tsai1, Chieri Tomomori-Sato2, Shigeo Sato2
1Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
Cell
|June 3, 2014
概括
研究人员绘制了中介体综合体的结构和子单元组织,揭示了对基因表达调节至关重要的大规模重组. 这一突破澄清了在真核生物中转录启动的机制.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 多个子单元的中间体复合体 (大约. 30种蛋白质) 对基因表达,桥接转录因子和RNA聚合酶II (RNAPII) 是至关重要的.
- 了解调解者的机制一直受到其结构,子单位组织和构造动态的知识不足的限制.
研究的目的:
- 阐明中介体复合体的结构,子单位组织和构造性重组.
- 为转录调节中介作用提供一个全面的模型.
主要方法:
- 低温电子显微镜 (EM) 用于确定酵母和人类中间体复合物的高分辨率结构.
- 小单位定位实验和部分X射线结构的对接.
- 生物化学分析以绘制子单元相互作用和组织的地图.
主要成果:
- 获得了酵母和人类中介体复合物的精确EM结构,克服了以前的技术障碍.
- 酵母媒介子单位的全面映射和其整体组织模型的重新解释.
- 识别了大规模的介质重组,取决于模块接口的变化,由转录启动因子促进.
结论:
- 介质结构,子单元组织和RNAPII相互作用在真核生物中得到保护.
- 揭示了转录启动所必需的中介机制的基本方面.
- 为了解分子层面的基因表达调节提供了基础.
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