Huang Meixian, Xu Qinghong, Mitsui Kazuhiro, Xu Zhaojun
Quanzhou Medical College, Quanzhou, Fujian, China; The Second Department of Biochemistry, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan.
FEMS Microbiol Lett. 2014 Jan;350(2):154-60. doi: 10.1111/1574-6968.12329. Epub 2013 Dec 2.
The Per-ARNT-Sim (PAS) domain serine/threonine kinase PAS kinase is involved in energy flux and protein synthesis. In yeast, PSK1 and PSK2 are two partially redundant PASK homologs. We recently generated PSK2 deletion mutant and showed that Psk2 acts as a nutrient-sensing protein kinase to modulate Ultradian clock-coupled respiratory oscillation in yeast. Here, we show that deletion of PSK1 increased the sensitivity of yeast cells to oxidative stress (H2 O2 treatment) and partially inhibited cell growth; however, the growth of the PSK2-deleted mutant was similar to that of the wild type. Superoxide dismutase-1 (SOD1) mRNA and protein levels were lower in PSK1-deletion mutant than the wild type. The mRNA levels of stress response genes CTT1, HSP104, ATH1, NTH1 and SOD2 were similar in both the PSK1-deleted mutant and wild-type yeast. Furthermore, intracellular accumulation of reactive oxygen species (ROS) was noted in PSK1-deleted mutant. These results suggest that PSK1 induces SOD1 expression to protect against oxidative stress in yeast.
Per-ARNT-Sim（PAS）结构域丝氨酸/苏氨酸激酶PAS激酶参与能量代谢和蛋白质合成。在酵母中，PSK1和PSK2是两个部分冗余的PASK同源物。我们最近构建了PSK2缺失突变体，并表明Psk2作为一种营养感应蛋白激酶来调节酵母中超日节律时钟耦合的呼吸振荡。在此，我们表明PSK1的缺失增加了酵母细胞对氧化应激（过氧化氢处理）的敏感性并部分抑制了细胞生长；然而，PSK2缺失突变体的生长与野生型相似。超氧化物歧化酶-1（SOD1）的mRNA和蛋白水平在PSK1缺失突变体中低于野生型。应激反应基因CTT1、HSP104、ATH1、NTH1和SOD2的mRNA水平在PSK1缺失突变体和野生型酵母中相似。此外，在PSK1缺失突变体中观察到活性氧（ROS）的细胞内积累。这些结果表明，PSK1诱导SOD1表达以保护酵母免受氧化应激。
