Abstract：
Yeasts have been widely used as a model to better understand cell cycle mechanisms and how nutritional and genetic factors can impact cell cycle progression. While nitrogen scarcity is well known to modulate cell cycle progression, the relevance of nitrogen excess for microorganisms has been overlooked. In our previous work, we observed an absence of proper entry into the quiescent state in Hanseniaspora vineae and identified a potential link between this behavior and nitrogen availability. Furthermore, the Hanseniaspora genus has gained attention due to a significant loss of genes associated with DNA repair and cell cycle. Thus, the aim of our study was to investigate the effects of varying nitrogen concentrations on H. vineae\'s cell cycle progression. Our findings demonstrated that nitrogen excess, regardless of the source, disrupts cell cycle progression and induces G2/M arrest in H. vineae after reaching the stationary phase. Additionally, we observed a viability decline in H. vineae cells in an ammonium-dependent manner, accompanied by increased production of reactive oxygen species, mitochondrial hyperpolarization, intracellular acidification, and DNA fragmentation. Overall, our study highlights the events of the cell cycle arrest in H. vineae induced by nitrogen excess and attempts to elucidate the possible mechanism triggering this absence of proper entry into the quiescent state.
摘要：
酵母已被广泛用作更好地理解细胞周期机制以及营养和遗传因素如何影响细胞周期进程的模型。众所周知，氮缺乏可以调节细胞周期进程，氮过量与微生物的相关性被忽视了。在我们之前的工作中,我们观察到Hanseniaspora葡萄科没有适当进入静止状态，并确定了这种行为与氮利用率之间的潜在联系。此外，由于与DNA修复和细胞周期相关的基因的大量丢失，Hanseniaspora属已获得关注。因此，本研究的目的是研究不同氮浓度对H.vineae细胞周期进程的影响。我们的发现表明氮过量，不管来源,在达到稳定期后，在H.vineae中破坏细胞周期进程并诱导G2/M停滞。此外,我们观察到H.vineae细胞以铵依赖性方式的生存力下降，伴随着活性氧的产生增加，线粒体超极化,细胞内酸化，和DNA片段化。总的来说,我们的研究重点介绍了氮过量引起的H.vineae细胞周期停滞事件,并试图阐明引发这种缺乏进入静止状态的可能机制.
