Conserved and divergent features of kinetochores and spindle microtubule ends from five species.
Conserved and divergent features of kinetochores and spindle microtubule ends from five species.
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DOI：
10.1083/jcb.201209154
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发表时间：
2013-02-18
期刊：
影响因子：
--
通讯作者：
Grishchuk EL
中科院分区：
文献类型：
--
作者：
McIntosh JR;O'Toole E;Zhudenkov K;Morphew M;Schwartz C;Ataullakhanov FI;Grishchuk EL
对动粒-微管界面的全面、跨物种的电子断层扫描分析提供了对共同的结构特征及其可能的功能后果的洞察。用电子断层扫描和图像分析对不同物种的纺锤体微管和动心之间的界面进行了观察。哺乳动物、藻类、线虫和两种酵母菌的整体结构都是保守的；它们都没有致密的外板，大多数动粒微管末端张开成弯曲的原丝，通过细长的纤维连接到染色质上。对8,500根原丝的曲率分析表明，所有级别的纺锤体微管都显示出一些张开的原丝，包括那些生长在后期区间的原丝。后期动粒微管上弯曲的原丝并不比中期微管更张开，但更长。发芽酵母中张开的原丝由纤维连接到类似核小体的密度；这些很可能是酵母的动粒。分裂酵母中相似的密度更大，定义更不明确，但两种酵母都显示出环状或部分环状结构，包裹着它们的动粒微管。与染色质相连的张开的原丝处于很好的位置，可以对染色体施加力量，确保稳定的附着和可靠的后期分离。
A comprehensive, cross-species electron tomography analysis of kinetochore–microtubule interfaces has provided insight into shared structural features and their likely functional consequences. Interfaces between spindle microtubules and kinetochores were examined in diverse species by electron tomography and image analysis. Overall structures were conserved in a mammal, an alga, a nematode, and two kinds of yeasts; all lacked dense outer plates, and most kinetochore microtubule ends flared into curved protofilaments that were connected to chromatin by slender fibrils. Analyses of curvature on >8,500 protofilaments showed that all classes of spindle microtubules displayed some flaring protofilaments, including those growing in the anaphase interzone. Curved protofilaments on anaphase kinetochore microtubules were no more flared than their metaphase counterparts, but they were longer. Flaring protofilaments in budding yeasts were linked by fibrils to densities that resembled nucleosomes; these are probably the yeast kinetochores. Analogous densities in fission yeast were larger and less well-defined, but both yeasts showed ring- or partial ring-shaped structures girding their kinetochore microtubules. Flaring protofilaments linked to chromatin are well placed to exert force on chromosomes, assuring stable attachment and reliable anaphase segregation.
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影响因子：
1.6
作者：
ALBERTSON, DG;THOMSON, JN
通讯作者：
THOMSON, JN
影响因子：
4
作者：
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4
作者：
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影响因子：
3
作者：
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影响因子：
7.8
作者：
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通讯作者：
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