Deciphering Dynamic Dose Responses of Natural Promoters and Single cis Elements upon Osmotic and Oxidative Stress in Yeast
Deciphering Dynamic Dose Responses of Natural Promoters and Single cis Elements upon Osmotic and Oxidative Stress in Yeast
复制标题
DOI：
10.1128/mcb.00240-13
复制
发表时间：
2013-06-01
影响因子：
5.3
通讯作者：
Proft, Markus
中科院分区：
文献类型：
--
作者：
Dolz-Edo, Laura;Rienzo, Alessandro;Proft, Markus
基因表达在应激反应中的精细激活是转录因子与特定启动子结合位点动态相互作用的结果。在这里描述的研究中，我们在活的酿酒酵母细胞中使用了时间分辨荧光素酶报告试验，以深入了解渗透和氧化应激信号如何以剂量敏感的方式调节基因表达。具体而言，四种不同的天然启动子（GRE2、CTT1、SOD2和CCP1）的剂量反应行为揭示了它们对不同盐和氧化刺激的敏感性和动力学差异。对于仅由一种类型的应力调节共识元件驱动的人工启动子，如环amp响应元件、应力响应元件或AP-1位点，也获得了典型的剂量响应曲线。氧化和渗透胁迫信号分别通过不同的信号分子以不同的灵敏度激活这些元素。应力激活顺式元件的组合通常不会提高绝对表达水平；然而，特定的组合可以增加启动子对不同应激剂量的诱导性。最后，我们表明，在氧化应激的情况下，细胞的应激耐受性关键调节其转录反应的动态。
Fine-tuned activation of gene expression in response to stress is the result of dynamic interactions of transcription factors with specific promoter binding sites. In the study described here we used a time-resolved luciferase reporter assay in living Saccharomyces cerevisiae yeast cells to gain insights into how osmotic and oxidative stress signals modulate gene expression in a dose-sensitive manner. Specifically, the dose-response behavior of four different natural promoters (GRE2, CTT1, SOD2, and CCP1) reveals differences in their sensitivity and dynamics in response to different salt and oxidative stimuli. Characteristic dose-response profiles were also obtained for artificial promoters driven by only one type of stress-regulated consensus element, such as the cyclic AMP-responsive element, stress response element, or AP-1 site. Oxidative and osmotic stress signals activate these elements separately and with different sensitivities through different signaling molecules. Combination of stress-activated cis elements does not, in general, enhance the absolute expression levels; however, specific combinations can increase the inducibility of the promoter in response to different stress doses. Finally, we show that the stress tolerance of the cell critically modulates the dynamics of its transcriptional response in the case of oxidative stress.