细胞mRNA3'-end处理机器的架构
Ana Casañal1, Ananthanarayanan Kumar1, Chris H Hill1
1MRC Laboratory of Molecular Biology, Cambridge, UK.
Science (New York, N.Y.)
|October 28, 2017
概括
研究人员阐明了酵母分裂和多化因子 (CPF) 聚合酶模块的结构. 这一发现揭示了酶如何协调处理信使RNA (mRNA) 3'端.
科学领域:
- 分子生物学
- 生物化学
- 结构生物学
背景情况:
- 细胞前体信使RNA (mRNA前体) 经历了至关重要的3'-end处理.
- 多蛋白分裂和多化因子 (CPF) 调解了前mRNA分裂,多化和转录终止.
- 目前尚不清楚CPF酶活性的精确协调和组合.
研究的目的:
- 研究酵母CPF的结构结构.
- 通过CPF阐明mRNA3'-end处理协调的机制.
- 要确定CPF聚合酶模块的结构.
主要方法:
- 使用电子冷显微镜 (cryo-EM) 来确定CPF聚合酶模块的结构.
- 为了验证功能方面,进行了体外复制实验.
- 结构分析侧重于聚合酶模块内的蛋白质组件的排列.
主要成果:
- 酵母CPF的核酶,聚合酶和酸酶活动分为三个不同的模块.
- 确定了大约200千多CPF聚合酶模块的3.5安斯特罗姆分辨率结构.
- 聚合酶模块具有四个β螺旋,类似于其他核酸结合蛋白质复合体.
- 聚合酶模块促进了聚烯酸尾的特定和高效添加.
结论:
- 确定的结构为CPF酶的协调作用提供了见解.
- 聚合酶模块在聚合精确聚化所必需的因素中发挥着关键作用.
- 这项研究提高了我们对真核生物3'-end处理调节的理解.
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