Kinesin motors provide the molecular forces at the kinetochore-microtubule interface and along the spindle to control chromosome segregation. During meiosis with two rounds of microtubule assembly-disassembly, the roles of motor proteins remain unexplored. We observed that in contrast to mitosis, Cin8 and Kip3 together are indispensable for meiosis. While examining meiosis in cin8Δ kip3Δ cells, we detected chromosome breakage in the meiosis II cells. The double mutant exhibits a delay in cohesin removal during anaphase I. Consequently, some cells fail to undergo meiosis II and form dyads, while some, as they progress through meiosis II, cause a defect in chromosome integrity. We believe that in the latter cells, an imbalance of spindle-mediated force and the simultaneous persistence of cohesin on chromosomes cause their breakage. We provide evidence that tension generated by Cin8 and Kip3 through microtubule cross-linking is essential for signaling efficient cohesin removal and the maintenance of chromosome integrity during meiosis.

中文翻译：

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驱动蛋白马达在出芽酵母中粘连蛋白去除和染色体完整性维持中的减数分裂特异性功能。


驱动蛋白马达在动粒-微管界面和沿着纺锤体提供分子力来控制染色体分离。在有两轮微管组装-拆卸的减数分裂过程中，运动蛋白的作用仍未被探索。我们观察到，与有丝分裂相反，Cin8 和 Kip3 一起对于减数分裂是不可或缺的。在检查 cin8Δ kip3Δ 细胞的减数分裂时，我们检测到减数分裂 II 细胞中的染色体断裂。双突变体在后期 I 期间表现出粘连蛋白去除的延迟。因此，一些细胞无法经历减数分裂 II 并形成二分体，而有些细胞在经历减数分裂 II 时会导致染色体完整性缺陷。我们认为，在后一种细胞中，纺锤体介导的力的不平衡和染色体上粘连蛋白的同时持续存在导致了它们的断裂。我们提供的证据表明，Cin8 和 Kip3 通过微管交联产生的张力对于发出有效的粘连蛋白去除信号和维持减数分裂过程中染色体完整性至关重要。