Cdc2 phosphorylation of the fission yeast Dis1 ensures accurate chromosome segregation
Cdc2 phosphorylation of the fission yeast Dis1 ensures accurate chromosome segregation
复制标题
DOI：
10.1016/j.cub.2006.06.065
复制
发表时间：
2006-08-22
期刊：
影响因子：
9.2
通讯作者：
Yanagida, Mitsuhiro
中科院分区：
文献类型：
--
作者：
Aoki, Keita;Nakaseko, Yukinobu;Yanagida, Mitsuhiro
缩短的着丝点微管在后期将分离的染色单体运送到相对的纺锤极。裂变酵母Dis1属于Dis1/XMAP215/TOG家族，这是适当微管动力学所必需的。在这里，我们报道了Dis1受Cdc2磷酸化的调控，并且这种有丝分裂磷酸化确保了染色体分离的保真度。突变体Dis1（6A）和Dis1（6E）分别用6个Cdc2位点代替Ala或Glu，在22℃-36℃产生菌落，而Dis1（6A）而不是Dis1（6E）失去一条小染色体，并以显著的频率显示异常染色体分离。Dis1（WT）被招募到有丝分裂纺锤体的两个区域：中期的着丝点（也可能是着丝点微管）和后期的极对极微管晶格。突变体Dis1（6E）优先结合中期着丝点，而位于微管沿线的Dis1（6A）在着丝点的积累减少。Dis1（6A）与mis12-537一起显示合成致死性，mis12-537是一种损害着丝点功能的突变体。Dis1（6E）模仿cdc2磷酸化形式的Dis1(WT)，而Dis1（6A）可以部分挽救导致Mtc1/AIp14（另一种xmap215样蛋白）缺失的表型。在后期，去磷酸化的Disl和Dis1(6A)，而不是Dis1(6E)，移动到spb附近的纺锤体微管晶格。因此，Cdc2直接磷酸化Dis1，这种磷酸化调节Dis1在中期和后期的定位，并确保高保真分离。
Shortened kinetochore microtubules take separated chromatids to the opposing spindle poles in anaphase. Fission yeast Dis1 belongs to the Dis1/XMAP215/TOG family that is required for proper microtubule dynamics. Here, we report that Dis1 is regulated by Cdc2 phosphorylation and that this mitotic phosphorylation ensures the fidelity of chromosome segregation. Whereas mutants Dis1(6A) and Dis1(6E) that substitute all of the six Cdc2 sites for Ala or Glu, respectively, produce colonies at 22 degrees C-36 degrees C, Dis1(6A) but not Dis1(6E) loses a minichromosome and reveals aberrant chromosome segregation at significant frequencies. Dis1(WT) is recruited to two regions of the mitotic spindle: kinetochores (possibly also kinetochore microtubules) in metaphase and the pole-to-pole microtubule lattice in anaphase. Mutant Dis1(6E) preferentially binds to metaphase kinetochores, whereas Dis1(6A), which is located along microtubules, falls in its accumulation at kinetochores. Dis1(6A) displays synthetic lethality with the mis12-537, which is a mutant that compromises kinetochore function. Dis1(6E) mimics the Cdc2-phosphorylated form of Dis1(WT), whereas Dis1(6A) can partially rescue the phenotype resulting form deletion of Mtc1/AIp14, another XMAP215-like protein. In anaphase, dephosphorylated Disl and Dis1(6A), but not Dis1(6E), move to the spindle microtubule lattice near the SPBs. Cdc2 thus directly phosphorylates Dis1, and this phosphorylation regulates Disl localization in both metaphase and anaphase and ensures high-fidelity segregation.