Turchetti Benedetta, Marconi Gianpiero, Sannino Ciro, Buzzini Pietro, Albertini Emidio
Department of Agricultural, Food and Environmental Sciences, University of Perugia, Borgo XX Giugno, 74, 06121 Perugia, Italy.
Microorganisms. 2020 Feb 20;8(2):296. doi: 10.3390/microorganisms8020296.
The involvement of DNA methylation in the response to cold stress of two different yeast species (, psychrophilic, and , psychrotolerant), exhibiting different temperature aptitudes, has been studied. Consecutive incubations at respective optimum temperatures, at 4 °C (cold stress) and at optimum temperatures again, were performed. After Methylation Sensitive Amplified Polymorphism (MSAP) fingerprints a total of 550 and 423 clear and reproducible fragments were amplified from and strains, respectively. The two strains showed a different response in terms of level of DNA methylation during cold stress and recovery from cold stress. The percentage of total methylated fragments in psychrophilic did not show any significant change. On the contrary, the methylation of psychrotolerant exhibited a nonsignificant increase during the incubation at 4 °C and continued during the recovery step, showing a significant difference if compared with control condition, resembling an uncontrolled response to cold stress. A total of 12 polymorphic fragments were selected, cloned, and sequenced. Four fragments were associated to genes encoding for elongation factor G and for chitin synthase export chaperon. To the best of our knowledge, this is the first study on DNA methylation in the response to cold stress carried out by comparing a psychrophilic and a psychrotolerant yeast species.
研究了DNA甲基化在两种具有不同温度适应性的酵母（嗜冷酵母和耐冷酵母）对冷胁迫反应中的作用。分别在各自的最适温度、4℃（冷胁迫）以及再次回到最适温度下进行连续培养。通过甲基化敏感扩增多态性（MSAP）指纹图谱分析，分别从嗜冷酵母和耐冷酵母菌株中扩增出550个和423个清晰且可重复的片段。两种酵母菌株在冷胁迫期间以及从冷胁迫恢复过程中的DNA甲基化水平表现出不同的反应。嗜冷酵母中总甲基化片段的百分比没有显示出任何显著变化。相反，耐冷酵母在4℃培养期间甲基化呈现出不显著的增加，并在恢复阶段持续增加，与对照条件相比显示出显著差异，类似于对冷胁迫的失控反应。总共选择了12个多态性片段进行克隆和测序。其中四个片段与编码延伸因子G和几丁质合酶输出伴侣蛋白的基因相关。据我们所知，这是首次通过比较嗜冷酵母和耐冷酵母物种来研究DNA甲基化在对冷胁迫反应中的作用。
