International Journal of Biosciences, vol.15, no.5, pp.241-248, 2019 (Peer-Reviewed Journal)
Trehalose is an important storage carbohydrate for Saccharomyces cerevisiae. It protects yeast cells from physiological stresses. Trehalose also controls glucose transport to yeast cells by acting on hexokinase. When trehalose is over accumulated or during the recovery stage of the yeast cells from stress, neutral trehalase enzyme which is encoded by NTH1 gene degrades trehalose to restore normal growth conditions. Hence trehalase enzyme is essential for balanced levels of trehalose and for normal metabolic activities of the yeast cells. TOR (Target of rapamycin) signaling pathway activates many cellular processes and signaling pathways under normal growth conditions in yeast. Besides rapamycine, caffeine treatment and certain stress conditions inhibits TOR pathway. In this research the effects of various signal transduction pathways on the promoter activities of NTH1 gene and on the reserve carbohydrate metabolism were investigated during nutrient limitation and nutrient replenishment periods in S. cerevisiae. The results showed that the transcription of NTH1 gene is transiently activated during nutrient replenishment period. Our results also suggest that cAMP dependent PKA and TOR signaling pathways may involve in the transcriptional regulation of NTH1 gene.