Cell cycle control of spindle pole body duplication and splitting by Sfi1 and Cdc31 in fission yeast
Cell cycle control of spindle pole body duplication and splitting by Sfi1 and Cdc31 in fission yeast
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DOI：
10.1242/jcs.159657
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发表时间：
2015-04-15
影响因子：
4
通讯作者：
Paoletti, Anne
中科院分区：
文献类型：
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作者：
Bouhlel, Imene B.;Ohta, Midori;Paoletti, Anne
纺锤体极的生物发生和分离紧密协调，以产生两极有丝分裂纺锤体。在酵母中，由Sfi1和Cdc31组成的纺锤体极体(SPB)半桥重复，促进第二个SPB的生物发生。在裂殖酵母中，Sfi1在半桥上分两个阶段积累，即从分裂后期到分裂早期，以及整个G2期。我们发现，Sfi1-CDc31在SPB复制中的作用是在分离结束和G2积累开始之前完成的。因此，Sfi1在有丝分裂出口处的早期积累可能对应于半桥复制。我们进一步表明，CDK1(由cdc2编码)共有位点上的丝氨酸15上的CDc31磷酸化是重要的Sfi1池从桥上解离和在有丝分裂开始时及时分离SPBS所必需的。这表明在裂解酵母中，CDC31N末端调控Sfi1-CDC31阵列的稳定性，并影响纺锤体双极性的建立时间。
Spindle pole biogenesis and segregation are tightly coordinated to produce a bipolar mitotic spindle. In yeasts, the spindle pole body (SPB) half-bridge composed of Sfi1 and Cdc31 duplicates to promote the biogenesis of a second SPB. Sfi1 accumulates at the half-bridge in two phases in Schizosaccharomyces pombe, from anaphase to early septation and throughout G2 phase. We found that the function of Sfi1-Cdc31 in SPB duplication is accomplished before septation ends and G2 accumulation starts. Thus, Sfi1 early accumulation at mitotic exit might correspond to half-bridge duplication. We further show that Cdc31 phosphorylation on serine 15 in a Cdk1 (encoded by cdc2) consensus site is required for the dissociation of a significant pool of Sfi1 from the bridge and timely segregation of SPBs at mitotic onset. This suggests that the Cdc31 N-terminus modulates the stability of Sfi1-Cdc31 arrays in fission yeast, and impacts on the timing of establishment of spindle bipolarity.