The Mitotic Exit Network Regulates Spindle Pole Body Selection During Sporulation of Saccharomyces cerevisiae
The Mitotic Exit Network Regulates Spindle Pole Body Selection During Sporulation of Saccharomyces cerevisiae
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DOI：
10.1534/genetics.116.194522
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发表时间：
2017-04
期刊：
影响因子：
3.3
通讯作者：
Christian Renicke;A. Allmann;A. Lutz;T. Heimerl;Christof Taxis
中科院分区：
文献类型：
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作者：
Christian Renicke;A. Allmann;A. Lutz;T. Heimerl;Christof Taxis
真核细胞中中心体的年龄遗传与不对称细胞分裂中染色体的忠实分布有关。在酿酒酵母子囊孢子形成过程中，这种遗传机制针对的是酵母中心体的等价物，即减数分裂II开始时的纺锤体极体(SPBS)。养分利用率的降低只会导致较年轻的SPBS及其相关基因组的孢子形成。这种机制确保了非姐妹基因组的封装，从而保持了遗传多样性，并在种群水平上提供了适应度优势。在这里，通过使用一种用于孢子形成诱导蛋白耗竭的增强系统，我们证明了核心有丝分裂退出网络(MEN)参与了基于年龄的SPB选择。此外，有效的基因组遗传需要在孢子成熟的后期阶段使用Dbf2/20-Mob1。我们提供的证据表明，这些男性的减数分裂功能比之前认为的要复杂得多。与有丝分裂相反，减数分裂的完成并不完全依赖于男性，而它的活动是在孢子发育的不同时间点所需的。这让人想起植物人在纺锤体极性建立、有丝分裂退出和胞质分裂中的作用。总之，我们的研究有助于理解酿酒酵母产孢子过程中基于年龄的SPB遗传，并在专门的发育计划的背景下提供关于网络可塑性的一般见解。此外，用于诱导蛋白质耗竭的特定发育工具的改进系统将在其他生物学环境中有用。
Age-based inheritance of centrosomes in eukaryotic cells is associated with faithful chromosome distribution in asymmetric cell divisions. During Saccharomyces cerevisiae ascospore formation, such an inheritance mechanism targets the yeast centrosome equivalents, the spindle pole bodies (SPBs) at meiosis II onset. Decreased nutrient availability causes initiation of spore formation at only the younger SPBs and their associated genomes. This mechanism ensures encapsulation of nonsister genomes, which preserves genetic diversity and provides a fitness advantage at the population level. Here, by usage of an enhanced system for sporulation-induced protein depletion, we demonstrate that the core mitotic exit network (MEN) is involved in age-based SPB selection. Moreover, efficient genome inheritance requires Dbf2/20-Mob1 during a late step in spore maturation. We provide evidence that the meiotic functions of the MEN are more complex than previously thought. In contrast to mitosis, completion of the meiotic divisions does not strictly rely on the MEN whereas its activity is required at different time points during spore development. This is reminiscent of vegetative MEN functions in spindle polarity establishment, mitotic exit, and cytokinesis. In summary, our investigation contributes to the understanding of age-based SPB inheritance during sporulation of S. cerevisiae and provides general insights on network plasticity in the context of a specialized developmental program. Moreover, the improved system for a developmental-specific tool to induce protein depletion will be useful in other biological contexts.