在缺乏动粒纤维下的染色体集合.docVIP

Chromosome congression in the absence of kinetochore fibres ——在缺乏动粒纤维下的染色体集合 Christopher B. O’Connell , Alexey Khodjakov and Claire E. Walczak conjunction 克里斯托夫奥康奈尔，阿列克谢Khodjakov和Claire瓦尔恰克 Proper chromosome congression (the process of aligning chromosomes on the spindle) contributes to accurate and faithful chromosome segregation. It is widely accepted that congression requires kinetochore fibres (K-fibres), microtubule bundles that extend from the kinetochores to spindle poles . 正确的染色体集合（调整染色体在主轴上的进程）有助于准确，忠实的染色体分离。人们普遍认为中板集合需要动粒纤维（K -纤维），是从动粒延长到主轴两极微管束。 Here, we demonstrate that chromosomes in human cells co- depleted of HSET (human kinesin-14) and hNuf2 (human Ndc80/Hec1-complex component) can congress to the metaphase plate in the absence of K-fibres. However, the chromosomes are not stably maintained at the metaphase plate under these conditions. Chromosome congression in HSET + hNuf2 co-depleted cells required the plus-end directed motor CENP-E (centromere protein E; kinesin-7 family 6-member) , which has been implicated in the gliding of mono- oriented kinetochores alongside adjacent K-fibres . 在这里，我们表明，HSET（人力驱动蛋白- 14）和hNuf2（人类5Ndc80/Hec1-复合物组件）都耗尽的人类细胞中，在缺乏K纤维时，染色体可以向赤道板集合。然而，染色体在这些条件下不能稳定的维持在中期。染色体集合在HSET + hNuf2都耗尽的细胞需要的加末定向运动着丝粒蛋白- E（中心体蛋白E，驱动蛋白- 7系列6成员），是动粒沿着相邻的K纤维做单向滑行所涉及的一类蛋白质。 Thus, proper end-on attachment of kinetochores to microtubules is not necessary for chromosome congression. Instead, our data support the idea that congression allows unattached chromosomes to move to the middle of the spindle where they have a higher probability of establishing connections with both spindle poles. These bi-oriented connections are also used to maintain stable chromosome alignment at the spindle equator. 因此，适当的结束微管动粒附件对染色体集合不是必需的。相反，我们的数据支持中板集合允许没有接触的染色体移动到主轴，在那里他们有建立与主轴两极联系的更大可能。这些双向拉伸的连接也被用来维持稳定的染色体在主轴赤道的一致。 The assembly of a functional mitotic spindle involves the process of chromosome congression, which positions all chromosom