Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France.
Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.
Elife. 2018 Jul 4;7:e34025. doi: 10.7554/eLife.34025.
Coordination of cell growth with division is essential for proper cell function. In budding yeast, although some molecular mechanisms responsible for cell size control during G1 have been elucidated, the mechanism by which cell size homeostasis is established remains to be discovered. Here, we developed a new technique based on quantification of histone levels to monitor cell cycle progression in individual cells with unprecedented accuracy. Our analysis establishes the existence of a mechanism controlling bud size in G2/M that prevents premature onset of anaphase, and controls the overall size variability. While most G1 mutants do not display impaired size homeostasis, mutants in which cyclin B-Cdk regulation is altered display large size variability. Our study thus demonstrates that size homeostasis is not controlled by a G1-specific mechanism alone but is likely to be an emergent property resulting from the integration of several mechanisms that coordinate cell and bud growth with division.
细胞生长与分裂的协调对于细胞正常功能至关重要。在出芽酵母中，虽然已经阐明了一些负责 G1 期间细胞大小控制的分子机制，但细胞大小稳态建立的机制仍有待发现。在这里，我们开发了一种基于组蛋白水平定量的新技术，以前所未有的精度来监测单个细胞的细胞周期进程。我们的分析确立了存在一种控制 G2/M 中芽大小的机制，该机制可防止过早进入后期，并控制整体大小变异性。虽然大多数 G1 突变体没有显示出受损的大小稳态，但细胞周期蛋白 B-Cdk 调节发生改变的突变体显示出较大的大小变异性。因此，我们的研究表明，大小稳态不是由单一的 G1 特异性机制控制的，而是可能是整合几个协调细胞和芽生长与分裂的机制的结果。
