TY - JOUR AU - Turgut Genç, Tülay AU - GÜNAY, Melih PY - 2022/04/30 Y2 - 2024/03/29 TI - TRANSCRIPTOMIC ANALYSIS OF GLYCOGEN METABOLISM AFTER CAFFEINE TREATMENT IN Saccharomyces cerevisiae JF - International Journal of Natural and Engineering Sciences JA - ijnes VL - 16 IS - 1 SE - Articles DO - UR - https://ijnes.org/index.php/ijnes/article/view/659 SP - 1-10 AB - <p>Saccharomyces cerevisiae is used as a model organism for investigating the metabolic and<br />genetic regulations in higher organisms. Glycogen is a storage carbohydrate in yeast cells and is used as<br />an energy source. Glycogen is accumulated at the onset of the stationary phase and the logarithmic phase<br />during different environmental and intracellular stress conditions. Glycogen level in the cell is regulated<br />by different sensory and signaling pathways. TOR signaling pathway is activated when the environmental<br />conditions are suitable, but it is repressed after rapamycin/caffeine treatment or nutrient starvation. In this<br />study, the effect of the TOR signaling pathway on glycogen metabolism was determined with the Next<br />Generation Sequencing method in S. cerevisiae. The total RNA isolated from yeast cells grown in a<br />medium containing caffeine was used for the Next Generation Sequencing analysis. The differentially<br />expressed genes after caffeine treatment were determined by comparing the caffeine-treated cells to<br />untreated cells. It was determined that the transcription of 44% of the genes was expressed differentially<br />after caffeine treatment, and 20% of differentially expressed genes were found to be up-regulated. The<br />transcription of genes involved in glycogen metabolism, except PGM1, was up-regulated after caffeine<br />treatment. The inactivation of Tor1p caused to increase in PGM2, UGP1, GLG1, GSY1, GSY2, GLC3,<br />GPH1, and GDB1 transcription at least 2 fold. In silico analysis revealed that these genes include at least<br />one STRE sequence in their promoter regions for binding of Msn2/4 transcription factors. It was observed<br />that after caffeine treatment MSN2 transcription was down-regulated while MSN4 transcription was<br />upregulated. This indicates that the Msn4 transcription factor was more effective than Msn2p in upregulating genes in glycogen metabolism. In conclusion, repression of the TOR signaling pathway by<br />caffeine causes Msn4p-dependent transcriptional activation of genes involved in glycogen metabolism.</p> ER -