论文标题
饥饿细菌中细胞尺寸波动的比例不变性
Scale invariance of cell size fluctuations in starving bacteria
论文作者
论文摘要
在稳定的环境中，细胞大小的波动被认为是由简单的物理原理支配的，如最近的缩放特性发现所暗示的那样。在这里，通过开发微流体设备并使用大肠杆菌，我们研究了细胞大小波动对饥饿的响应。通过突然切换到非整合培养基，我们发现细胞尺寸的分布发生变化，但满足规模不变性：重新分布的分布保持不变并取决于饥饿之前的生长条件。这些发现是基于细胞生长和细胞周期的模型的基础。此外，我们在数值上确定了饥饿过程中各个特征时间的量表不变性的有效性范围，并发现违反慢速饥饿的规模不变性。我们的结果与理论参数相结合，提出了多部复制的相关性，这有助于保留细胞周期状态的信息，因此可能导致规模不变性。
In stable environments, cell size fluctuations are thought to be governed by simple physical principles, as suggested by recent findings of scaling properties. Here, by developing a microfluidic device and using E. coli, we investigate the response of cell size fluctuations against starvation. By abruptly switching to non-nutritious medium, we find that the cell size distribution changes but satisfies scale invariance: the rescaled distribution is kept unchanged and determined by the growth condition before starvation. These findings are underpinned by a model based on cell growth and cell cycle. Further, we numerically determine the range of validity of the scale invariance over various characteristic times of the starvation process, and find the violation of the scale invariance for slow starvation. Our results, combined with theoretical arguments, suggest the relevance of the multifork replication, which helps retaining information of cell cycle states and may thus result in the scale invariance.
