在12个子单元核外体复合体中的RNA降解路径
Debora Lika Makino1, Benjamin Schuch1, Elisabeth Stegmann1
1Department of Structural Cell Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
Nature
|July 30, 2015
概括
现在可以理解真核外体是关键的RNA降解复合体,可以降解或切割RNA. 结构研究揭示了外体中的一个摇摆机制,它根据基质相互作用决定了RNA处理.
科学领域:
- 分子生物学
- 结构生物学
- 生物化学
背景情况:
- 细胞外体是一个重要的多子单元复合体,负责RNA降解,监测和处理.
- 外基因组实现完整的RNA降解和RNA基质的特定切割的确切机制尚不清楚.
研究的目的:
- 阐明真核外体的双RNA处理能力的结构基础.
- 了解外基因组如何区分完整的降解和精确的RNA剪切.
主要方法:
- 确定酵母核外体复合体 (12个子单元) 与各种RNA分子相关的晶体结构.
- 使用结构和生化分析的组合来研究RNA外体相互作用.
主要成果:
- 揭示了单链RNA如何直接访问RRp44或RRp6的活性位点.
- 通过外体的中央通道向Rrp44活性部位传递RNA.
- 观察到Rrp6-Rrp47模块的形状变化 (摆动机制),当重的RNA阻碍了通道入口时.
结论:
- 外基因组采用一种依赖于RNA的摇摆机制,涉及其RNase子单元来协调过程性降解和部分修剪.
- 这种机制解释了单个分子机器如何根据RNA基质特征执行不同的RNA处理结果.
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