Arslan Mevlüt, Holyavkin Can, Kısakesen Halil İbrahim, Topaloğlu Alican, Sürmeli Yusuf, Çakar Zeynep Petek
Department of Molecular Biology and Genetics, Faculty of Science & Letters, Istanbul Technical University, Maslak, 34469, Istanbul, Turkey.
Dr. Orhan Öcalgiray Molecular Biology, Biotechnology and Genetics Research Center (İTÜ-MOBGAM), Istanbul Technical University, Maslak, Istanbul, Turkey.
Mol Biotechnol. 2018 Jul;60(7):468-484. doi: 10.1007/s12033-018-0087-2.
High-throughput aging studies with yeast as a model organism involve transposon-mutagenesis and yeast knockout collection, which have been pivotal strategies for understanding the complex cellular aging process. In this study, a chronologically long-lived Saccharomyces cerevisiae mutant was successfully obtained by using another high-throughput approach, evolutionary engineering, based on systematic selection in successive batch cultures under gradually increasing levels of caloric restriction. Detailed comparative physiological and transcriptomic analyses of the chronologically long-lived mutant and the reference strain revealed enhanced levels of respiratory metabolism, upregulation of genes related to carbohydrate metabolic processes, glycogen-trehalose pathways, stress response, and repression of protein synthesis-related genes in the long-lived mutant SRM11, already in the absence of caloric restriction. Interestingly, SRM11 had also significantly higher resistance to copper stress, and higher resistance to silver, ethanol, and 2-phenylethanol stresses than the reference strain. It also had lower ethanol production levels and an enhanced ethanol catabolism. To conclude, evolutionary engineering is another powerful high-throughput method for aging research, in addition to its widespread use in industrial strain development. Additionally, the interesting results revealed by this study about the potential relationship between longevity and various cellular properties are yet to be investigated further at molecular level.
以酵母作为模式生物的高通量衰老研究涉及转座子诱变和酵母基因敲除文库，这些都是理解复杂细胞衰老过程的关键策略。在本研究中，基于在逐渐增加热量限制水平的连续分批培养中进行系统选择，通过另一种高通量方法——进化工程，成功获得了一株时序寿命长的酿酒酵母突变体。对该时序寿命长的突变体和参考菌株进行详细的比较生理学和转录组分析发现，在不存在热量限制的情况下，长寿突变体SRM11中呼吸代谢水平增强，与碳水化合物代谢过程、糖原-海藻糖途径、应激反应相关的基因上调，以及与蛋白质合成相关的基因受到抑制。有趣的是，SRM11对铜胁迫的抗性也显著更高，并且对银、乙醇和2-苯乙醇胁迫的抗性高于参考菌株。它的乙醇产生水平也较低，乙醇分解代谢增强。总之，进化工程是衰老研究中的另一种强大的高通量方法，此外它还广泛应用于工业菌株开发。此外，本研究揭示的关于寿命与各种细胞特性之间潜在关系的有趣结果，还有待在分子水平上进一步研究。
