Three-dimensional structure of a pre-catalytic human spliceosomal complex B
Three-dimensional structure of a pre-catalytic human spliceosomal complex B
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DOI：
10.1038/nsmb761
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发表时间：
2004-05-01
影响因子：
16.8
通讯作者：
Stark, H
中科院分区：
文献类型：
--
作者：
Boehringer, D;Makarov, EM;Stark, H
在剪接体从完全组装的复合物 B 转变为催化激活剪接体的过程中，发生了主要的结构变化。为了理解重排，有必要了解这些配合物的详细三维结构。在这里，我们在 U4/U6.U5 tri-snRNP 整合后但激活前的阶段获得了免疫亲和纯化的人类剪接体（命名为 BDeltaU1），并通过单粒子电子冷冻显微镜以类似于 40 埃的分辨率确定了 BDeltaU1 的三维结构。建筑群的整体尺寸约为 370 x 270 x 170 埃。三维结构的特点是大致呈三角形的主体以可变方向与头部域相连。该体的大小和形状与分离的 U4/U6.U5 tri-snRNP 非常相似。这提供了对复合体 B 的结构组织的初步了解。
Major structural changes occur in the spliceosome during its transition from the fully assembled complex B to the catalytically activated spliceosome. To understand the rearrangement, it is necessary to know the detailed three-dimensional structures of these complexes. Here, we have immunoaffinity-purified human spliceosomes (designated BDeltaU1) at a stage after U4/U6.U5 tri-snRNP integration but before activation, and have determined the three-dimensional structure of BDeltaU1 by single-particle electron cryomicroscopy at a resolution of similar to40 Angstrom. The overall size of the complex is about 370 x 270 x 170 Angstrom. The three-dimensional structure features a roughly triangular body linked to a head domain in variable orientations. The body is very similar in size and shape to the isolated U4/U6.U5 tri-snRNP. This provides initial insight into the structural organization of complex B.