Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, Italy.
SYSBIO, Centre of Systems Biology, Milan, Italy.
Sci Rep. 2018 Apr 11;8(1):5853. doi: 10.1038/s41598-018-24252-y.
Before anaphase onset, budding yeast cells must align the mitotic spindle parallel to the mother-bud axis to ensure proper chromosome segregation. The protein kinase Snf1/AMPK is a highly conserved energy sensor, essential for adaptation to glucose limitation and in response to cellular stresses. However, recent findings indicate that it plays important functions also in non-limiting glucose conditions. Here we report a novel role of Snf1/AMPK in the progression through mitosis in glucose-repressing condition. We show that active Snf1 is localized to the bud neck from bud emergence to cytokinesis in a septin-dependent manner. In addition, loss of Snf1 induces a delay of the metaphase to anaphase transition that is due to a defect in the correct alignment of the mitotic spindle. In particular, genetic data indicate that Snf1 promotes spindle orientation acting in parallel with Dyn1 and in concert with Kar9. Altogether this study describes a new role for Snf1 in mitosis and connects cellular metabolism to mitosis progression.
在后期开始之前，芽殖酵母细胞必须使有丝分裂纺锤体与母细胞-芽细胞轴平行排列，以确保染色体的正确分离。蛋白激酶 Snf1/AMPK 是一种高度保守的能量传感器，对于适应葡萄糖限制和响应细胞应激至关重要。然而，最近的研究结果表明，它在非限制葡萄糖条件下也发挥着重要作用。在这里，我们报告了 Snf1/AMPK 在葡萄糖抑制条件下有丝分裂进程中的新作用。我们表明，在有隔孢酵母中，活性 Snf1 从出芽到胞质分裂都以依赖于 septin 的方式定位于芽颈。此外，Snf1 的缺失会导致中期到后期的转变延迟，这是由于有丝分裂纺锤体的正确排列出现缺陷。特别是，遗传数据表明，Snf1 通过与 Dyn1 平行并与 Kar9 协调作用来促进纺锤体定向，从而促进纺锤体定向。总之，这项研究描述了 Snf1 在有丝分裂中的一个新作用，并将细胞代谢与有丝分裂进程联系起来。
