D'Aquino Katharine E, Monje-Casas Fernando, Paulson Jennifer, Reiser Vladimir, Charles Georgette M, Lai Leslie, Shokat Kevan M, Amon Angelika
Howard Hughes Medical Institute, Center for Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Mol Cell. 2005 Jul 22;19(2):223-34. doi: 10.1016/j.molcel.2005.06.005.
Accurate nuclear position is essential for each daughter cell to receive one DNA complement. In budding yeast, a surveillance mechanism known as the spindle position checkpoint ensures that exit from mitosis only occurs when the anaphase nucleus is positioned along the mother-bud axis. We identified the protein kinase Kin4 as a component of the spindle position checkpoint. KIN4 prevents exit from mitosis in cells with mispositioned nuclei by inhibiting the mitotic exit network (MEN), a GTPase signaling cascade that promotes exit from mitosis. Kin4 is active in cells with mispositioned nuclei and predominantly localizes to mother cells, where it is ideally situated to inhibit MEN signaling at spindle pole bodies (SPBs) when anaphase spindle elongation occurs within the mother cell.
精确的细胞核位置对于每个子细胞接收一套DNA互补物至关重要。在出芽酵母中，一种称为纺锤体位置检查点的监测机制可确保只有当后期细胞核沿母细胞-芽轴定位时才会发生有丝分裂退出。我们鉴定出蛋白激酶Kin4是纺锤体位置检查点的一个组成部分。KIN4通过抑制有丝分裂退出网络（MEN）来阻止细胞核位置错误的细胞退出有丝分裂，MEN是一种促进有丝分裂退出的GTPase信号级联反应。Kin4在细胞核位置错误的细胞中具有活性，并且主要定位于母细胞，当后期纺锤体在母细胞内伸长时，它在那里的位置理想，能够在纺锤极体（SPB）处抑制MEN信号传导。
