Yang Emily J, Pernice Wolfgang M, Pon Liza A
Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA.
iScience. 2022 Feb 23;25(3):103957. doi: 10.1016/j.isci.2022.103957. eCollection 2022 Mar 18.
Babies are born young, largely independent of the age of their mothers. Mother-daughter age asymmetry in yeast is achieved, in part, by inheritance of higher-functioning mitochondria by buds and retention of some high-functioning mitochondria in mother cells. The mitochondrial F box protein, Mfb1p, tethers mitochondria at both poles in a cell cycle-regulated manner: it localizes to and anchors mitochondria at the mother cell tip throughout the cell cycle and at the bud tip before cytokinesis. Here, we report that cell polarity and polarized localization of Mfb1p decline with age in . Moreover, deletion of genes (, and ) that mediate symmetry breaking during establishment of cell polarity and asymmetric yeast cell division cause depolarized Mfb1p localization and defects in mitochondrial distribution and quality control. Our results support a role for the polarity machinery in lifespan through modulating Mfb1 function in asymmetric inheritance of mitochondria during yeast cell division.
婴儿出生时年幼，很大程度上与母亲的年龄无关。酵母中母女年龄不对称部分是通过芽继承功能更高的线粒体以及母细胞中保留一些高功能线粒体来实现的。线粒体F盒蛋白Mfb1p以细胞周期调控的方式将线粒体拴在两极：在整个细胞周期中它定位于母细胞顶端并将线粒体锚定在该位置，在胞质分裂前定位于芽顶端。在这里，我们报告在……中细胞极性和Mfb1p的极化定位会随着年龄增长而下降。此外，介导细胞极性建立和酵母细胞不对称分裂过程中对称性打破的基因（……和……）的缺失会导致Mfb1p定位去极化以及线粒体分布和质量控制缺陷。我们的结果支持极性机制通过在酵母细胞分裂期间调节线粒体不对称遗传中的Mfb1功能在寿命中发挥作用。
