Regulation of NDR1 activity by PLK1 ensures proper spindle orientation in mitosis

作者：Maomao Yan, Lingluo Chu, Bo Qin, Zhikai Wang, Xing Liu, Changjiang Jin, Guanglan Zhang, Marta Gómez-Ferrer, Alexander Hergovich, Zhengjun Chen, Ping He, Xinjiao Gao, Xuebiao Yao · 发表于：Scientific Reports · 年份：2015 · DOI：10.1038/srep10449 · 被引用次数：27 · 研究领域：Hippo pathway signaling and YAP/TAZ、Microtubule and mitosis dynamics、14-3-3 protein interactions

Accurate chromosome segregation during mitosis requires the physical separation of sister chromatids which depends on correct position of mitotic spindle relative to membrane cortex. Although recent work has identified the role of PLK1 in spindle orientation, the mechanisms underlying PLK1 signaling in spindle positioning and orientation have not been fully illustrated. Here, we identified a conserved signaling axis in which NDR1 kinase activity is regulated by PLK1 in mitosis. PLK1 phosphorylates NDR1 at three putative threonine residues (T7, T183 and T407) at mitotic entry, which elicits PLK1-dependent suppression of NDR1 activity and ensures correct spindle orientation in mitosis. Importantly, persistent expression of non-phosphorylatable NDR1 mutant perturbs spindle orientation. Mechanistically, PLK1-mediated phosphorylation protects the binding of Mob1 to NDR1 and subsequent NDR1 activation. These findings define a conserved signaling axis that integrates dynamic kinetochore-microtubule interaction and spindle orientation control to genomic stability maintenance.