核孔关联的TREX-2复合体使用调节器来调节基因表达
Maren Schneider1, Doris Hellerschmied2, Tobias Schubert1
1Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter Campus (VBC), Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria.
Cell
|August 29, 2015
概括
该TREX-2复合体与调解器复合体相互作用,调节基因转录和mRNA输出. 这一发现揭示了核孔综合体如何通过连接转录和RNA处理来影响基因表达.
科学领域:
- 分子生物学
- 细胞生物学
- 基因调控
背景情况:
- 核孔复合体 (NPC) 调节细胞核与细胞质之间的运输.
- 位于NPC篮子中的TREX-2复合体影响基因表达,转录和mRNA输出.
- TREX-2 调节基因表达机制的确切机制尚不清楚.
研究的目的:
- 阐明TREX-2复合体调节基因表达的机制.
- 研究TREX- 2与Mediator复合体之间的相互作用,这是RNA聚合酶II (Pol II) 的关键调节剂.
主要方法:
- 结构和生化研究以确定与Mediator的TREX-2相互作用区域.
- 用Cdk8激酶组合的中间体分析.
- 对Pol II的招募和酸化进行评估.
- 为了评估TREX-2和Med31的相互依赖性,转录组和表型分析.
- 研究TREX-2在mRNA出口中的作用.
主要成果:
- TREX-2 通过一个保存区域直接结合介质Med31/Med7N子模块.
- TREX-2 通过 Cdk8 激酶调节介质组合.
- TREX-2对于Pol II的招募和特定地点的化是必不可少的.
- 在特定的基因中显示TREX-2和Med31的功能相互依赖.
- TREX-2利用其介质相互作用表面来调节mRNA输出,链接转录和mRNA处理.
结论:
- TREX-2 作为一个通过中间体复合体访问核心转录机制的适配器复合体.
- TREX-2 将转录启动与早期的mRNA处理步骤相结合.
- 这项研究提供了NPC相关因素如何调节基因表达的机制性见解.
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