Abstract:
Most of microbe cells spend the majority of their times in quiescence due to unfavorable environmental conditions. The study of this dominant state is crucial for understanding the basic cell physiology. Retained recovery ability is a critical property of quiescent cells, which consists of two features: how long the cells can survive (the survivability) and how fast they can recover (the recovery activity). While the survivability has been extensively studied under the background of chronological aging, how the recovery activity depends on the quiescent time and what factors influence its dynamics have not been addressed quantitatively. In this work, we systematically quantified both the survivability and the recovery activity of long-lived quiescent fission yeast cells at the single cell level under various nutrient conditions. It provides the most profound evolutionary dynamics of quiescent cell regeneration ability described to date. We found that the single cell recovery time linearly increased with the starvation time before the survivability significantly declined. This linearity was robust under various nutrient conditions and the recovery speed was predetermined by the initial nutrient condition. Transcriptome profiling further revealed that quiescence states under different nutrient conditions evolve in a common trajectory but with different speed. Our results demonstrated that cellular quiescence has a continuous spectrum of depths and its physiology is greatly influenced by environmental conditions.
摘要:
由于不利的环境条件,大多数微生物细胞的大部分时间都处于静止状态。对这种优势状态的研究对于理解基本的细胞生理学至关重要。保留恢复能力是静态电池的关键属性,它包括两个特征:细胞可以存活多长时间(生存能力)和它们可以恢复多快(恢复活动)。虽然在时间老化的背景下对生存能力进行了广泛的研究,恢复活动如何取决于静止时间以及影响其动力学的因素尚未定量解决。在这项工作中,我们在各种营养条件下,在单细胞水平上系统地定量了长寿命静态裂变酵母细胞的生存能力和恢复活性。它提供了迄今为止描述的静止细胞再生能力的最深刻的进化动力学。我们发现,单细胞恢复时间随着饥饿时间的线性增加,生存能力才显著下降。这种线性在各种营养条件下是稳健的,并且恢复速度由初始营养条件预先确定。转录组分析进一步表明,不同营养条件下的静止状态以共同的轨迹演变,但速度不同。我们的结果表明,细胞静止具有连续的深度谱,其生理学受环境条件的影响很大。