Chromosome motion and the spindle matrix.
Chromosome motion and the spindle matrix.
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染色体运动和主轴矩阵。
DOI：
10.1083/jcb.99.1.137s
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发表时间：
1984-07
影响因子：
7.8
通讯作者：
Tippit, D
中科院分区：
文献类型：
--
作者：
Pickett-Heaps, J;Spurck, T;Tippit, D
在有丝分裂过程中，可以区分三种有丝分裂运动。它们共同负责染色体分离。(For为了达到我们目前的目的，我们将忽略几种不太常见的运动，这些运动还不太清楚，例如前期染色体的运动。染色体运动通常在前中期开始，此时形成的纺锤体侵入核质。微管（MTs）和染色体之间的前中期相互作用产生第一种类型的运动，不规则的染色体振荡最初指向导致中期板构型的任一极。分裂后期通常包括两个不同的阶段（36）：分裂后期A将染色体移动到极点，而在分裂后期B，纺锤体伸长。在本文中，我们主要考虑前中期和后期A运动。一旦Inoue和他的合作者（19）证明纺锤体纤维存在于活细胞中，细胞学家就可以概念化与有丝分裂运动相关的结构框架。戊二醛固定的出现使得有可能确定这些纺锤体纤维含有MT。在大多数细胞中，一部分MT终止于动粒。这种结构关系立即与其他证据相关联，这些证据表明动粒是染色体附着在纺锤体上的部位，在那里向极的力施加在染色体上。这些插入的MT已经被着丝粒成核或聚合的推论得到了生物化学（在参考文献30中总结）和细胞学观察的广泛支持，但最近对这一观点进行了重新评估。此外，附件ofMT的动粒表明，他们是机械功能，在移动动粒极。这两个结论中的一个或两个都隐含在有丝分裂的几个模型中。虽然问题尚未决定，但我们认为这两个非常有影响力的结论是不正确的，因此目前的纺锤体模型可能存在根本性缺陷（30）。所有这些著名的模型的另一个严重缺点是，除了最简单的术语外，它们无法解释有丝分裂现象;例如，染色体复杂、不稳定的前中期活动就无法得到令人满意的解释。我们选择了两个方面的许多概念COM-
During mitosis, three kinds of mitotic movement can be distinguished. Collectively they are responsible for chromosome separation.(For our present purposes, we will ignore several less common motions that are poorly understood, such as those of prophase chromosome movement.) Chromosome motion usually commences during prometaphase when the forming spindle invades the nucleoplasm. The consequent prometaphase interaction between microtubules (MTs)'and chromosomes generates the first type of motion, irregular chromosome oscillations directed initially at either pole that lead to the metaphase plate configuration. Anaphase usually involves two distinct phases (36): anaphase A moves the chromosomes to the pole, and during anaphase B, the spindle elongates. In this paper, we consider mainly prometaphase and anaphase A movements. Once Inoue and collaborators (19) had shown that spindle fibers exist in living cells, cytologists could conceptualize the structural framework associated with mitotic movements. The advent ofglutaraldehyde fixation made it possible to establish that these spindle fibers contain MTs. In most cells, a proportion ofthe MTs terminate in the kinetochores. This structural relationship was immediately correlated with other evidence suggesting that the kinetochores are the site of chromosome attachment to the spindle, where poleward forces are exerted upon the chromosomes. The deduction that these inserted MTs had been nucleated or polymerized by the kinetochore has received widespread support from biochemical (summarized in reference 30) and cytological observations, but recently there has been a reappraisal ofthis viewpoint. Furthermore, the attachment ofMTs to the kinetochore suggests that they are mechanically functional in moving the kinetochore to the pole. Either or both of these conclusions are implicit in several models of mitosis. Although the issues are not yet decided, we believe that these two very influential conclusions are incorrect, and so current models ofthe spindle may be fundamentally flawed (30). Another serious shortcoming of all the well-known models is their inability to explain mitotic phenomena in all but the simplest terms; for example, the complex, erratic prometaphase activity of chromosomes has defied satisfactory explanation. We have chosen two aspects of the many conceptual com-