Dormancy is colloquially considered as extending lifespan by being still. Starved yeasts form dormant spores that wake‐up (germinate) when nutrients reappear but cannot germinate (die) after some time. What sets their lifespans and how they age are open questions because what processes occur—and by how much—within each dormant spore remains unclear. With single‐cell‐level measurements, we discovered how dormant yeast spores age and die: spores have a quantifiable gene‐expressing ability during dormancy that decreases over days to months until it vanishes, causing death. Specifically, each spore has a different probability of germinating that decreases because its ability to—without nutrients—express genes decreases, as revealed by a synthetic circuit that forces GFP expression during dormancy. Decreasing amounts of molecules required for gene expression—including RNA polymerases—decreases gene‐expressing ability which then decreases chances of germinating. Spores gradually lose these molecules because they are produced too slowly compared with their degradations, causing gene‐expressing ability to eventually vanish and, thus, death. Our work provides a systems‐level view of dormancy‐to‐death transition.

中文翻译：

---

酵母孢子从休眠到死亡的转变是由于基因表达能力的逐渐丧失而发生的

休眠通俗地被认为是通过静止来延长寿命。饥饿的酵母会形成休眠孢子，当营养物质重新出现时，孢子会苏醒（发芽），但一段时间后就无法发芽（死亡）。是什么决定了它们的寿命以及它们如何衰老都是悬而未决的问题，因为每个休眠孢子内发生了什么过程以及发生的程度仍然不清楚。通过单细胞水平的测量，我们发现了休眠的酵母孢子如何衰老和死亡：孢子在休眠期间具有可量化的基因表达能力，这种能力会在数天到数月内下降，直至消失，导致死亡。具体来说，每个孢子都有不同的发芽概率，这种概率会降低，因为在没有营养的情况下，它表达基因的能力会下降，正如在休眠期间强制 GFP 表达的合成电路所揭示的那样。基因表达所需的分子数量（包括 RNA 聚合酶）的减少会降低基因表达能力，从而降低发芽的机会。孢子逐渐失去这些分子，因为与降解相比，它们的产生速度太慢，导致基因表达能力最终消失，从而死亡。我们的工作提供了休眠到死亡转变的系统级视图。