In vivo protein architecture of the eukaryotic kinetochore with nanometer scale accuracy.
In vivo protein architecture of the eukaryotic kinetochore with nanometer scale accuracy.
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DOI：
10.1016/j.cub.2009.02.056
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发表时间：
2009-04-28
期刊：
影响因子：
--
通讯作者：
Salmon ED
中科院分区：
文献类型：
--
作者：
Joglekar AP;Bloom K;Salmon ED
着丝点是一种大分子蛋白质机器，它将着丝染色质连接到一个或多个微管（MT）的正端，并在细胞分裂过程中分离染色体。其核心结构由8个多组分蛋白质复合物组成，其中大部分在所有真核生物中都是保守的。我们使用了体内双色荧光显微镜技术，首次在纳米分辨率下确定了这些蛋白质沿着出芽酵母着丝点轴的位置。与着丝点蛋白计数一起，这些定位预测了着丝点-微管附着的三维蛋白质结构，并提供了新的功能见解。我们还发现，随着中期张力的丧失，着丝点在后期变得短得多。缩短主要是由于Ndc80配合物的长度减少，这可能是由于Ndc80配合物在Ndc80/Nuf2二聚体柄区扭结处的分子内弯曲或其相对于微管轴的取向改变所致。Ndc80和Mtw1复合物内的构象变化可能作为MT附着和纺锤体组装检查点的张力依赖性调节的机械线索。本文报道的出芽酵母着丝点的核心结构与哺乳动物着丝点的几何结构非常相似，这表明真核生物的着丝点结构和区域着丝点结构都是保守的。
The kinetochore is a macromolecular protein machine that links centromeric chromatin to the plus-ends of one or more microtubules (MT), and segregates chromosomes during cell division. Its core structure consists of eight multi-component protein complexes, most of which are conserved in all eukaryotes. We use an in vivo two-color fluorescence microscopy technique to determine, for the first time, the location of these proteins along the budding yeast kinetochore axis at nanometer resolution. Together with kinetochore protein counts, these localizations predict the 3-D protein architecture of a kinetochore-microtubule attachment, and provide new functional insights. We also find that the kinetochore becomes much shorter in anaphase as metaphase tension is lost. Shortening is mainly due to a decrease in the length of the Ndc80 complex, which may result either from intra-molecular bending of the Ndc80 complex at the kink within the stalk region of the Ndc80/Nuf2 dimer or from a change in its orientation relative to the microtubule axis. Conformational changes within the Ndc80 and Mtw1 complexes may serve as mechanical cues for tension-dependent regulation of MT attachment and the spindle assembly checkpoint. The geometry of the core structure of the budding yeast kinetochore reported here is remarkably similar to that found in mammalian kinetochores, indicating that kinetochore structure is conserved in eukaryotes with either point or regional centromeres.
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影响因子：
3.4
作者：
Thompson, RE;Larson, DR;Webb, WW
通讯作者：
Webb, WW
影响因子：
64.5
作者：
Ciferri, Claudio;Pasqualato, Sebastiano;Musacchio, Andrea
通讯作者：
Musacchio, Andrea
DOI：
10.1073/pnas.0405925102
发表时间：
2005-04-12
影响因子：
11.1
作者：
Bouck, DC;Bloom, KS
通讯作者：
Bloom, KS
影响因子：
1.6
作者：
Schittenhelm RB;Heeger S;Althoff F;Walter A;Heidmann S;Mechtler K;Lehner CF
通讯作者：
Lehner CF
影响因子：
16.8
作者：
Miranda, JJL;De Wulf, P;Harrison, SC
通讯作者：
Harrison, SC