Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
Department of Pharmacology and System Physiology, College of Medicine, University of Cincinnati, Cincinnati, OH 45219, USA.
Cells. 2022 Apr 26;11(9):1462. doi: 10.3390/cells11091462.
For correct chromosome segregation in mitosis, eukaryotic cells must establish chromosome biorientation where sister kinetochores attach to microtubules extending from opposite spindle poles. To establish biorientation, any aberrant kinetochore-microtubule interactions must be resolved in the process called error correction. For resolution of the aberrant interactions in error correction, kinetochore-microtubule interactions must be exchanged until biorientation is formed (the SWAP process). At initiation of biorientation, the state of weak kinetochore-microtubule interactions should be converted to the state of stable interactions (the SWITCH process)-the conundrum of this conversion is called the initiation problem of biorientation. Once biorientation is established, tension is applied on kinetochore-microtubule interactions, which stabilizes the interactions (the STABILIZE process). Aurora B kinase plays central roles in promoting error correction, and Mps1 kinase and Stu2 microtubule polymerase also play important roles. In this article, we review mechanisms of error correction by considering the SWAP, SWITCH, and STABILIZE processes. We mainly focus on mechanisms found in budding yeast, where only one microtubule attaches to a single kinetochore at biorientation, making the error correction mechanisms relatively simpler.
为了在有丝分裂中正确分离染色体，真核细胞必须建立染色体双定向，即姐妹动粒附着在从纺锤体两极延伸出的微管上。为了建立双定向，在称为错误修正的过程中，必须解决任何异常的动粒-微管相互作用。为了解决错误修正过程中的异常相互作用，必须通过动粒-微管相互作用的交换，直到形成双定向（SWAP 过程）。在双定向起始时，弱动粒-微管相互作用的状态应转换为稳定相互作用的状态（SWITCH 过程）——这种转换的难题称为双定向起始问题。一旦建立了双定向，就会在动粒-微管相互作用上施加张力，从而稳定相互作用（STABILIZE 过程）。Aurora B 激酶在促进错误修正中起着核心作用，Mps1 激酶和 Stu2 微管聚合酶也起着重要作用。在本文中，我们通过考虑 SWAP、SWITCH 和 STABILIZE 过程来回顾错误修正的机制。我们主要关注芽殖酵母中的机制，在芽殖酵母中，只有一条微管附着在双定向的单个动粒上，这使得错误修正机制相对更简单。
