在3.6安格斯特罗姆分辨率下的酵母结合体结构
Chuangye Yan1, Jing Hang1, Ruixue Wan1
1Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
Science (New York, N.Y.)
|August 22, 2015
概括
研究人员揭示了酵母结合体的3D结构, 这种复杂的机器对于基因表达至关重要. 这张接近原子分辨率的地图阐明了这种分子机械如何精确地拼接前传递RNA (前mRNA).
科学领域:
- 分子生物学
- 结构生物学
- 生物化学
背景情况:
- 前传递 RNA (前mRNA) 拼接是真核生物的一个基本过程,对基因表达至关重要.
- 拼接体是一个大型分子机器,催化了mRNA前拼接,由小核核蛋白质 (snRNP),相关蛋白质和RNA分子组成.
- 了解结合体的结构动态是阐明结合机制的关键.
研究的目的:
- 确定来自Schizosaccharomyces pombe的功能拼接体的三维结构.
- 提供高分辨率的分子框架,以了解mRNA前拼接的机制.
主要方法:
- 使用单粒子冷电子显微镜 (cryo-EM) 可视化结合体.
- 获得了近原子分辨率 (3.6安格斯特罗姆) 的结构.
- 一个包含蛋白质和RNA组件的原子模型.
主要成果:
- 在3.6安格斯特罗姆分辨率下确定了Schizosaccharomyces pombe spliceosome的三维结构.
- 该结构揭示了U2和U5snRNP的排列,十九个复合体 (NTC),NTC相关蛋白质 (NTR),U6小核RNA和RNA内核.
- 蛋白质Spp42 (Prp8同类) 被确定为一个中心支架,定催化中心.
结论:
- 接近原子分辨率的结构提供了前所未有的分子洞察力.
- 观察到的组件排列表明了有效的mRNA前拼接的进化适应.
- 这种结构框架对于前mRNA拼接的机制研究至关重要.
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