Jiang Hongyuan
Department of Modern Mechanics, CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei, Anhui 230026, China.
Sci Rep. 2015 May 27;5:10504. doi: 10.1038/srep10504.
Mitotic spindle is the main subcellular structure that accomplishes the chromosome segregation between daughter cells during cell division. However, how mitotic spindles sense and control their size, position and movement inside the cell still remains unclear. In this paper, we focus on the size effects of mitotic spindles, i.e., how cell size controls various interesting phenomena in the metaphase, such as oscillation, positioning and size limit of mitotic spindles. We systematically studied the frequency doubling phenomenon during chromosome oscillation and found that cell size can regulate the period and amplitude of chromosome oscillation. We found that the relaxation time of the positioning process increases exponentially with cell size. We also showed that the stabler microtubule-kinetochore attachments alone can directly lead to an upper limit of spindle size. Our work not only explains the existing experimental observations, but also provides some interesting predictions that can be verified or rejected by further experiments.
有丝分裂纺锤体是细胞分裂过程中实现子细胞间染色体分离的主要亚细胞结构。然而，有丝分裂纺锤体如何感知并控制其在细胞内的大小、位置和运动仍不清楚。在本文中，我们聚焦于有丝分裂纺锤体的大小效应，即细胞大小如何控制中期的各种有趣现象，如有丝分裂纺锤体的振荡、定位和大小限制。我们系统地研究了染色体振荡过程中的倍频现象，发现细胞大小可以调节染色体振荡的周期和幅度。我们发现定位过程的弛豫时间随细胞大小呈指数增加。我们还表明，仅更稳定的微管 - 动粒附着就能直接导致纺锤体大小的上限。我们的工作不仅解释了现有的实验观察结果，还提供了一些有趣的预测，可通过进一步实验进行验证或否定。
