Quantitative transcriptome analysis of a high-GSH producing Saccharomyces cerevisiae and the wild type based on the second generation sequencing.

The mutant Saccharomyces cerevisiae Y518 generated much more intracellular glutathione (GSH) than its counterpart dose. The RNA-seq based global transcriptome analysis was performed for exploring the potential mechanisms. Statistical analysis indicated that 1125 differentially expressed genes (fold-change>=2.0, FDR<=0.001) were up-regulated and 503 were down-regulated. There were 12 genes involved in glutathione metabolism. Of which GSH1, encodes gamma-glutamine cysteine synthetase, the rate-limiting enzyme in GSH biosynthesis process, was up-regulated. And MET17, encodes cysteine synthase A, an enzyme catalyzes the biosynthesis of one of the precursor amino acids L- cysteine, was also up-regulated. Besides, regulator SKN7 and several genes involved in oxidative stress response (GPX2, CTT1, SOD1, TRX2) were up-regulated. Intracellular ROS level of Y518 was also enhanced compared to that of 2-10515. Our results indicate that up-regulations of GSH1 and MET17 might be associated with the increased intracellular GSH content of the mutant, and up-regulated GSH1 may be caused by increased intracellular ROS level. Overall design: Saccharomyces cerevisiae mRNA profiles of 24-h wild type 2-10515 and mutant Y518 were generated by deep sequencing using Illumina HiSeqTM 2000

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