Global transcriptional response of wild type and transcription factor deletion strains of Saccharomyces cerevisiae to the environmental stress of cold shock and subsequent recovery

Previous studies on the global transcriptional response of budding yeast, Saccharomyces cerevisiae, to cold shock have revealed that the response can be divided into a set of early response genes (after 15 minutes to 2 hours of cold temperatures) and late response genes (after 12 to 60 hours of cold temperatures). The late response genes include the ESR genes induced by many environmental stresses and are regulated by the Msn2 and Msn4 transcription factors, as they are during other environmental stresses (Kandror et al. 2004 PMID:15053871; Schade et al. 2004 PMID:15483057). However, the transcription factors responsible for the induction of the early response genes, the overall regulatory mechanism governing this early response, and the transcriptional response to recovery after cold shock remain largely unknown. Thus, we measured the early transcriptional response of S. cerevisiae to cold shock and subsequent recovery using DNA microarrays. To determine which transcription factors were responsible for these changes in expression, the same cold shock and recovery microarray experiments were then performed on six strains individually deleted for the transcription factors Cin5, Gln3, Hap4, Hmo1, Swi4, and Zap1.过往针对酿酒酵母（Saccharomyces cerevisiae，又称出芽酵母）冷激下的全局转录响应的研究表明，该响应可分为早期响应基因（低温处理15分钟至2小时后）与晚期响应基因（低温处理12至60小时后）两类。晚期响应基因包含受多种环境应激诱导的环境应激响应（Environmental Stress Response, ESR）基因，其调控机制与其他环境应激情形下一致，均由Msn2和Msn4转录因子介导（Kandror等，2004，PMID:15053871；Schade等，2004，PMID:15483057）。然而，介导早期响应基因诱导的转录因子、调控该早期响应的整体调控机制，以及冷激后恢复过程中的转录响应，目前仍未得到充分阐明。为此，本研究采用DNA微阵列（DNA microarray）技术，检测了酿酒酵母对冷激及后续恢复过程的早期转录响应。为明确参与上述表达变化的转录因子，研究团队随后针对分别敲除Cin5、Gln3、Hap4、Hmo1、Swi4及Zap1这6种转录因子的单基因缺失菌株，重复开展了相同的冷激与恢复微阵列实验。